U.S. patent application number 17/042963 was filed with the patent office on 2021-03-25 for fully dull polyester drawn yarn and preparing method thereof.
This patent application is currently assigned to JIANGSU HENGLI CHEMICAL FIBRE CO., LTD.. The applicant listed for this patent is JIANGSU HENGLI CHEMICAL FIBRE CO., LTD.. Invention is credited to Feng CHEN, Xiaohua SUN, Lixin YIN.
Application Number | 20210087716 17/042963 |
Document ID | / |
Family ID | 1000005301876 |
Filed Date | 2021-03-25 |
United States Patent
Application |
20210087716 |
Kind Code |
A1 |
YIN; Lixin ; et al. |
March 25, 2021 |
FULLY DULL POLYESTER DRAWN YARN AND PREPARING METHOD THEREOF
Abstract
A type of fully dull polyester drawn yarns and a preparing
method thereof are disclosed. The preparing method is to melt
spinning a modified polyester with the fully drawn yarn (FDY)
technique, and the modified polyester is a product of an
esterification and successive polycondensation reactions of evenly
mixed terephthalic acid, ethylene glycol,
2,5,6,6-tetramethyl-2,5-heptanediol, a fluorinated dicarboxylic
acid, a matting agent, a calcined multiphase solid acid base powder
and a doped Bi.sub.2O.sub.3 powder. The obtained fiber has an
intrinsic viscosity drop of 18-26% when stored at 25.degree. C. and
R.H. 65% for 60 months. The method of improving the degradation
performance of polyester fiber through the incorporation of
2,5,6,6-tetramethyl-2,5-heptanediol, the fluorinated dicarboxylic
acid, the doped Bi.sub.2O.sub.3 powder and the calcined multiphase
solid acid base powder is easy to operate.
Inventors: |
YIN; Lixin; (Wujiang,
CN) ; CHEN; Feng; (Wujiang, CN) ; SUN;
Xiaohua; (Wujiang, CN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
JIANGSU HENGLI CHEMICAL FIBRE CO., LTD. |
Wujiang |
|
CN |
|
|
Assignee: |
JIANGSU HENGLI CHEMICAL FIBRE CO.,
LTD.
Wujiang
CN
|
Family ID: |
1000005301876 |
Appl. No.: |
17/042963 |
Filed: |
October 29, 2019 |
PCT Filed: |
October 29, 2019 |
PCT NO: |
PCT/CN2019/113843 |
371 Date: |
September 29, 2020 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C08K 3/36 20130101; C08K
2003/222 20130101; C08K 2003/2227 20130101; D01F 1/10 20130101;
C08K 3/22 20130101; C08G 63/46 20130101; C08G 63/6826 20130101;
C08G 63/866 20130101; D01F 6/92 20130101 |
International
Class: |
D01F 6/92 20060101
D01F006/92; C08G 63/86 20060101 C08G063/86; C08G 63/682 20060101
C08G063/682; D01F 1/10 20060101 D01F001/10; C08K 3/22 20060101
C08K003/22; C08K 3/36 20060101 C08K003/36; C08G 63/46 20060101
C08G063/46 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 27, 2018 |
CN |
201811614058.X |
Claims
1. A preparing method for a fully dull polyester drawn yarn,
comprising: manufacturing a fully drawn yarn (FDY) with a modified
polyester; wherein the modified polyester is a product of
esterification and successive polycondensation reactions of an
evenly mixed mixture of terephthalic acid, ethylene glycol,
2,5,6,6-tetramethyl-2,5-heptanediol, a fluorinated dicarboxylic
acid, a matting agent, a calcined multiphase solid acid base powder
and a doped Bi.sub.2O.sub.3 powder; wherein the
2,5,6,6-tetramethyl-2,5-heptanediol has a molecular formula of
##STR00003## wherein the fluorinated dicarboxylic acid is selected
from the group consisting of 2,2-difluoro-1,3-malonic acid,
2,2-difluoro-1,4-succinic acid, 2,2-difluoro-1,5-glutaric acid and
2,2,3,3-tetrafluoro-1,4-succinic acid; wherein the matting agent
has an additive amount equal to or larger than 2 wt % of the evenly
mixed mixture; wherein the calcined multiphase solid acid base
powder is SiO.sub.2--Al.sub.2O.sub.3 and/or SiO.sub.2--MgO calcined
at 400-700.degree. C.; wherein the doped Bi.sub.2O.sub.3 powder is
obtained through a process of evenly mixing a Ca.sup.2+ solution
and a Bi.sup.3+ solution to form an evenly mixed solution, then
adding a precipitant to the evenly mixed solution until pH=9-10 to
obtain a precipitate, and finally calcining the precipitate.
2. The preparing method of claim 1, wherein the Ca.sup.2+ solution
is an aqueous one with a concentration of 2-3%, an anion in the
Ca.sup.2+ solution is NO.sub.3.sup.-; wherein the Bi.sup.3+
solution is a product of dissolving 20-25 wt % of Bi.sub.2O.sub.3
in nitric acid; wherein the precipitant is ammonia water with a
concentration of 2 mol/L; wherein the evenly mixed solution has a
(5-8):100 molar ratio of Ca.sup.2+ with respective to Bi.sup.3+
before precipitation; wherein the calcining is a high temperature
treatment for 2-4 hrs; wherein the SiO.sub.2--Al.sub.2O.sub.3 or
SiO.sub.2--MgO has a SiO.sub.2 content of 20-60 wt % and an average
size of less than 0.5 micron after the calcining.
3. The preparing method of claim 2, wherein the
2,5,6,6-tetramethyl-2,5-heptanediol is synthesized by means of: (1)
mixing KOH, 3-methyl-3-hydroxybutyne, 3,3-dimethyl-2-butanone and
isopropyl ether in a molar ratio of (1-1.2):1:(1.2-1.3):(2.0-3.0),
then carrying out a first reaction in an ice bath for 2-4 hrs,
finally obtaining octyne diol through a series of processes of
cooling crystallization, centrifugation, washing, refining and
drying; (2) mixing the octyne diol, an alcohol and a Pd catalyst at
a weight ratio of (2-3):10:(0.01-0.03), then carrying out a second
reaction accompanied with a continuous hydrogen input at
40-50.degree. C. for 50-60 min, finally obtaining the
2,5,6,6-tetramethyl-2,5-heptanediol through a series of processes
of separation and purification.
4. The preparing method of claim 3, wherein the modified polyester
is manufactured through following steps: (1) Esterification
concocting the terephthalic acid, the ethylene glycol, the
2,5,6,6-tetramethyl-2,5-heptanediol and the fluorinated
dicarboxylic acid into a slurry, then adding the calcined
multiphase solid acid base powder, the doped Bi.sub.2O.sub.3
powder, a catalyst, the matting agent and a stabilizer in the
slurry and carrying out the esterification in a nitrogen atmosphere
with a pressure of normal value-0.3 MPa at 250-260.degree. C., and
finally ending the esterification when a water distillation rate
reaches more than 90% of a theoretical value; (2) Polycondensation
for products of the esterification, smoothly reducing the pressure
to less than 500 Pa (absolute value) within 30-50 min and carrying
out the successive polycondensation reactions at 250-260.degree. C.
for 30-50 min, further reducing the pressure to less than 100 Pa
(absolute value) and continuing the successive polycondensation
reactions at 270-282.degree. C. for 50-90 min.
5. The preparing method of claim 4, wherein a molar ratio of the
terephthalic acid and the ethylene glycol is 1:(1.2-2.0), and a
total addition of the 2,5,6,6-tetramethyl-2,5-heptanediol and the
fluorinated dicarboxylic acid is 3-5 mol % of an amount of the
terephthalic acid, a molar ratio of the
2,5,6,6-tetramethyl-2,5-heptanediol and the fluorinated
dicarboxylic acid is 2-3:3-4, while an amount of the calcined
multiphase solid acid base powder, the doped Bi.sub.2O.sub.3
powder, the catalyst, the matting agent and the stabilizer are
0.03-0.05 wt %, 0.04-0.07 wt %, 0.03-0.05 wt %, 2-3 wt % and
0.01-0.05 wt % of the amount of the terephthalic acid,
respectively.
6. The preparing method of claim 5, wherein the catalyst is
selected from the group consisting of antimony trioxide, ethylene
glycol antimony and antimony acetate, wherein the matting agent is
titanium dioxide, and wherein the stabilizer is selected from the
group consisting of triphenyl phosphate, trimethyl phosphate and
trimethyl phosphite.
7. The preparing method claim 6, wherein the modified polyester has
a molecular weight of 25000-30000 and a molecular weight
distribution index of 1.8-2.2.
8. The preparing method of claim 1, wherein a FDY technique process
includes the steps of metering, spinneret extruding, cooling,
oiling, stretching, heat setting and winding; wherein the FDY
process involves the following parameters: a spinning temperature
of 285-295.degree. C., a cooling temperature of 20-25.degree. C.,
an interlacing pressure of 0.20-0.30 MPa, a first godet roller
speed of 1600-1800 m/min, a first godet roller temperature of
70-80.degree. C., a second godet roller speed of 3000-3200 m/min, a
second godet roller temperature of 105-130.degree. C., a winding
speed of 2950-3130 m/min.
9. A fully dull polyester drawn yarn prepared by the preparing
method of claim 1, comprising: a modified polyester FDY; wherein
the modified polyester has a molecular chain structure composed of
terephthalic acid segments, ethylene glycol segments,
2,5,6,6-tetramethyl-2,5-heptanediol segments and fluorinated
dicarboxylic acid segments; wherein the modified polyester is
dispersed with the matting agent, the doped Bi.sub.2O.sub.3 powder
and the calcined multiphase solid acid base powder, and a content
of the matting agent is equal to or larger than 2 wt %.
10. The fully dull polyester drawn yarn of claim 9, wherein the
fully dull polyester drawn yan has mechanical performance indices
of a monofilament fineness 1.0-3.0 dtex, a breaking strength
.gtoreq.2.0 cN/dtex, an elongation at break 42.0.+-.4.0%, an
interlacing degree 19.+-.4/m, a linear density deviation rate
.ltoreq.1.0%, a breaking strength CV value %, a breaking elongation
CV value .ltoreq.10.0%, and a boiling water shrinkage rate
50.0.+-.10.5%; and has an intrinsic viscosity drop of 18-25% after
a storage at 25.degree. C. and R.H. 65% for 60 months.
11. The fully dull polyester drawn yarn of claim 9, wherein wherein
the Ca.sup.2+ solution is an aqueous one with a concentration of
2-3%, an anion in the Ca.sup.2+ solution is NO.sub.3.sup.-; wherein
the Bi.sup.3+ solution is a product of dissolving 20-25 wt % of
Bi.sub.2O.sub.3 in nitric acid; wherein the precipitant is ammonia
water with a concentration of 2 mol/L; wherein the evenly mixed
solution has a (5-8):100 molar ratio of Ca.sup.2+with respective to
Bi.sup.3+ before precipitation; wherein the calcining is a high
temperature treatment for 2-4 hrs; wherein the
SiO.sub.2--Al.sub.2O.sub.3 or SiO.sub.2--MgO has a SiO.sub.2
content of 20-60 wt % and an average size of less than 0.5 micron
after the calcining.
12. The fully dull polyester drawn yarn of claim 11, wherein the
2,5,6,6-tetramethyl-2,5-heptanediol is synthesized by means of: (1)
mixing KOH, 3-methyl-3-hydroxybutyne, 3,3-dimethyl-2-butanone and
isopropyl ether in a molar ratio of (1-1.2):1:(1.2-1.3):(2.0-3.0),
then carrying out a first reaction in an ice bath for 2-4 hrs,
finally obtaining octyne diol through a series of processes of
cooling crystallization, centrifugation, washing, refining and
drying; (2) mixing the octyne diol, an alcohol and a Pd catalyst at
a weight ratio of (2-3):10:(0.01-0.03), then carrying out a second
reaction accompanied with a continuous hydrogen input at
40-50.degree. C. for 50-60 min, finally obtaining the
2,5,6,6-tetramethyl-2,5-heptanediol through a series of processes
of separation and purification.
13. The fully dull polyester drawn yarn of claim 12, wherein the
modified polyester is manufactured through following steps: (1)
Esterification concocting the terephthalic acid, the ethylene
glycol, the 2,5,6,6-tetramethyl-2,5-heptanediol and the fluorinated
dicarboxylic acid into a slurry, then adding the calcined
multiphase solid acid base powder, the doped Bi.sub.2O.sub.3
powder, a catalyst, the matting agent and a stabilizer in the
slurry and carrying out the esterification in a nitrogen atmosphere
with a pressure of normal value-0.3 MPa at 250-260.degree. C., and
finally ending the esterification when a water distillation rate
reaches more than 90% of a theoretical value; (2) Polycondensation
for products of the esterification, smoothly reducing the pressure
to less than 500 Pa (absolute value) within 30-50 min and carrying
out the successive polycondensation reactions at 250-260.degree. C.
for 30-50 min, further reducing the pressure to less than 100 Pa
(absolute value) and continuing the successive polycondensation
reactions at 270-282.degree. C. for 50-90 min.
14. The fully dull polyester drawn yarn of claim 13, wherein a
molar ratio of the terephthalic acid and the ethylene glycol is
1:(1.2-2.0), and a total addition of the
2,5,6,6-tetramethyl-2,5-heptanediol and the fluorinated
dicarboxylic acid is 3-5 mol % of an amount of the terephthalic
acid, a molar ratio of the 2,5,6,6-tetramethyl-2,5-heptanediol and
the fluorinated dicarboxylic acid is 2-3:3-4, while an amount of
the calcined multiphase solid acid base powder, the doped
Bi.sub.2O.sub.3 powder, the catalyst, the matting agent and the
stabilizer are 0.03-0.05 wt%, 0.04-0.07 wt %, 0.03-0.05 wt %, 2-3
wt % and 0.01-0.05 wt % of the amount of the terephthalic acid,
respectively.
15. The fully dull polyester drawn yarn of claim 14, wherein the
catalyst is selected from the group consisting of antimony
trioxide, ethylene glycol antimony and antimony acetate, wherein
the matting agent is titanium dioxide, and wherein the stabilizer
is selected from the group consisting of triphenyl phosphate,
trimethyl phosphate and trimethyl phosphite.
16. The fully dull polyester drawn yarn of claim 15, wherein the
modified polyester has a molecular weight of 25000-30000 and a
molecular weight distribution index of 1.8-2.2.
17. The fully dull polyester drawn yarn of claim 9, wherein a FDY
process includes the steps of metering, spinneret extruding,
cooling, oiling, stretching, heat setting and winding; wherein the
FDY process involves the following parameters: a spinning
temperature of 285-295.degree. C., a cooling temperature of
20-25.degree. C., an interlacing pressure of 0.20-0.30 MPa, a first
godet roller speed of 1600-1800 m/min, a first godet roller
temperature of 70-80.degree. C., a second godet roller speed of
3000-3200 m/min, a second godet roller temperature of
105-130.degree. C., a winding speed of 2950-3130 m/min.
Description
CROSS REFERENCE TO THE RELATED APPLICATIONS
[0001] This application is the national phase entry of
International Application No. PCT/CN2019/113843, filed on Oct. 29,
2019, which is based upon and claims priority to Chinese Patent
Application No. 201811614058.X, filed on Dec. 27, 2018, the entire
contents of which are incorporated herein by reference.
TECHNICAL FIELD
[0002] The present invention belongs to the field of polyester
fiber, and more particularly, relates to one type of fully dull
polyester drawn yarns and preparing method thereof.
BACKGROUND
[0003] With the rapid expansion of polyester production capacity,
the world polyester fiber market has been full of competition with
a heavily squeezed profit margin. Only through the continuous
technological innovation to develop and manufacture the products
with high technology content and added value, can the polyester
fiber producers gain profits and keep market position. Concerning
polyethylene terephthalate (PET) fiber, differentiation and
functionalization has become the main industrial direction. Due to
their smooth surface and certain transparency, polyester fibers
tend to reflect most illumination light and show a dazzling and
uncomfortable luster, commonly known as glare. Fortunately, the
glare can be dimmed by guiding the reflective light to different
directions through a small amount of particles with heterologous
refractive index, which is usually called extinction treatment, and
the added material is known as matting agent. The fully dull fiber
has good shading performance and the relevant fabrics also have a
certain anti-ultraviolet capability, showing a good prospect and a
wider profit margin in the market.
[0004] In polyester fiber production, titania (TiO.sub.2) is widely
used as matting agent because of its high refractive index (2.60
prior to 1.00 of the air), chemical stability, good dispersion,
water-infusibility and durability against post-treatment and
washing. Furthermore, nano titania is a kind of stable, non-toxic
and tasteless ultraviolet absorbent. The fabric containing nano
titania has the function of anti ultraviolet suitable for sports
clothes, swimsuits, tents and so on. According to the market
research, there is a large demand for fully dull polyester filament
in the field of high-grade clothing and decoration, owing to the
soft handle, mild luster, bright color and good drape feeling
provided by the fully dull fabrics.
[0005] However, with the rapid development of PET industry,
although PET will not directly cause harm to the environment, the
difficulties in the PET waste treatment can indirectly increase
environmental pressure due to its huge amount and strong resistance
to atmospheric and microbial degradation. Actually, the number of
waste clothing is increasing year by year with the increasing
living standard, just in china nearly 30 million tons of waste
clothing are produced every year. At present, landfill,
incineration and recovery are the main methods to treat PET waste,
from the environmental protection point of view, landfill and
incineration are easy but dirty. Conversely, the degradation
recovery has been believed as an efficient and scientific treatment
for PET waste. However, the tight structure, the high crystallinity
and the long natural degradation time of PET bring much restriction
to the degradation recovery, and the highest proportion of
recycling for common PET fabric in U.S. is just about 13% whereas
in China that is even low as 10%. In practical application,
chemical degradation methods are mostly used for PET, including
hydrolysis and alcoholysis, as well as ammonolysis, amination and
pyrolysis, however, they are still far from solving the recycling
of a large number of waste clothing because of the problems such as
slow degradation rate and poor degradation effect. As matter of
fact, the natural degradation of clothing polyester fiber (PET
filament) has become an urgent problem in view of the needs of
environmental protection, resource conservation and sustainable
development.
[0006] Therefore, it is of great significance to develop a kind of
fully dull polyester drawn yarn with high degradation speed and
high degradation efficiency.
SUMMARY
[0007] The primary object of the present invention is to provide
one kind of fully dull polyester drawn yarn with high degradation
speed and high degradation efficiency as well as the preparing
method thereof, so as to overcome the inadequacies in the clothing
polyester fiber (PET filament) made from the existing
technology.
[0008] To this end, the key technical points of the invention are
as follows.
[0009] The preparing method of fully dull polyester drawn yarn is
to melt spinning a modified polyester with a fully drawn yarn (FDY)
technique; [0010] wherein said modified polyester is the product of
the esterification and the successive polycondensation reactions of
evenly mixed terephthalic acid, ethylene glycol,
2,5,6,6-tetramethyl-2,5-heptanediol, fluorinated dicarboxylic acid,
matting agent, calcined multiphase solid acid base powder and doped
Bi.sub.2O.sub.3 powder; [0011] wherein said
2,5,6,6-tetramethyl-2,5-heptanediol has a molecular formula as
[0011] ##STR00001## [0012] wherein said fluorinated dicarboxylic
acids could be 2,2-difluoro-1,3-malonic acid,
2,2-difluoro-1,4-succinic acid, 2,2-difluoro-1,5-glutaric acid or
2,2,3,3-tetrafluoro-1,4-succinic acid; [0013] wherein said matting
agent has an additive amount equal to or larger than 2 wt %;
[0014] wherein said multiphase solid acid base could be
SiO.sub.2-Al.sub.2O.sub.3 and/or SiO.sub.2--MgO calcined at
400-700.degree. C.; [0015] wherein said doped Bi.sub.2O.sub.3 is
obtained through a process of evenly mixing Ca.sup.2+ solution and
Bi.sup.3+ solution at first, then adding in the precipitant until
the pH=9-10, and finally calcining the precipitate.
[0016] Herein the polyester is modified by
2,5,6,6-tetramethyl-2,5-heptanediol, in which the tert-butyl groups
will change the segment movement mode, the inter-segment force and
the inter-segment distance of the polyester main chains so as to
enlarge the free volume. Large free volume is favorable to the
penetration of air or water into the polyester, hence can improve
its natural degradation performance to a certain extent.
[0017] Herein the natural degradation performance is further
improved by introducing silicated dicarboxylic acid, calcined
multiphase solid acid base powder and doped Bi.sub.2O.sub.3
powder.
[0018] Herein incorporated fluorinated dicarboxylic acid possesses
the characteristic of fluorine atom being bonded to .alpha.-C.
During the hydrolysis process of polyester, the electron cloud
density in the C--O bond is reduced by the electron-withdrawing
effect of .alpha.-C bonded fluorine atom hence the stability of the
tetrahedral anion intermediate formed by ester carbonyl together
with nucleophilic attacker will also decrease, which is conducive
to the nucleophilic addition reaction. Moreover, the steric
hindrance of fluorinated dicarboxylic acid is less than that of
terephthalic acid, which further promotes the nucleophilic addition
reaction. Therefore, the degradation based on the nucleophilic
addition of polyester will be significantly accelerated.
[0019] Herein incorporated Bi.sub.2O.sub.3 powder also has a
promotion effect on the natural degradation of polyester and the
mechanism is explained as follows. When oxygen reduction catalyst
is adopted in polyester, oxygen from air can penetrate into
polyester via the free volume, and the oxygen reduction reaction
will occur in the surface of catalyst to cause the broken of ester
bond, accordingly the polyester degradation will be promoted.
However, the further improvement of the degradation efficiency of
pure oxygen reduction catalyst is still limited. In the present
invention, calcium oxide doped Bi.sub.2O.sub.3, instead of the
mechanical mixture of calcium oxide and bismuth oxide, is dispersed
in the modified polyester. The crystal plane of Bi.sub.2O.sub.3
will be destroyed by calcium oxide doping, leading to the following
effects. On the one hand, the specific surface area of doped
Bi.sub.2O.sub.3 increases, which can improve the oxygen adsorption
capacity per unit mass of Bi.sub.2O.sub.3. Moreover, the oxygen
adsorption mode in the surface of doped Bi.sub.2O.sub.3 will change
to the side type adsorption from the end type adsorption in
original monoclinic Bi2O3, and the adsorption is not affected by
the steric hindrance of Bi atom in the surface. With the enhanced
chemical adsorption of O.sub.2 molecule at the Bi atom site and the
improved catalytic efficiency of oxygen reduction, the polyester
fiber containing doped Bi.sub.2O.sub.3 has a high degradation
efficiency, which is conducive to environmental protection.
[0020] Herein incorporated multiphase solid acid base can further
accelerate the degradation speed of polyester. On one hand, solid
base can combine with water to produce OH.sup.- ion with stronger
nucleophilic capacity than H.sub.2O, on the other hand, solid acid
can decompose to release H.sup.+ ion which can protonate the
carboxyl oxygen and make it easy to be attacked by a nucleophilic
agent with weak alkalinity such as H.sub.2O. Accordingly, the
problem in the common hydrolysis process of polyester without the
modification, such as the weak nucleophilic capacity of water and
the low polarity of carboxyl oxygen, could be solved by this
acid-base synergistic effect.
[0021] The preparation methods of SiO.sub.2--Al.sub.2O.sub.3 or
SiO.sub.2--MgO are list as follows:
[0022] adding 3-5wt % of disperser PEG 6000 into a sodium silicate
solution with an SiO.sub.2 equivalent concentration of 10-1 5wt %
and stirring the mixture at 40-50.degree. C. till be soluble, then
evenly adding in 10-1 5wt % of sulfuric acid solution till pH=10,
after aging for 0.5-1.0 hr continuing to add in sulfuric acid
solution till pH=8, heating the solution to 90-95.degree. C. and
aging for 2hr, filtering the solution under vacuum and washing the
residue with water until no SO4.sup.2- detection then further
washing with anhydrous ethanol for several times, finally drying
the product at 80-85.degree. C. and grinding it to obtain silica
powder;
[0023] adding 1 part of above silica powder into 50-60 parts of
water and stirring to disperse, then dripping in 2-3 parts of
aluminum sulfate or magnesium sulfate solution with a weight
concentration of 4-5%, adjusting the pH value firstly to neutral
and then to 8 with 0.5-1.0 mol/L sodium hydroxide solution and
8-10% sulfuric acid successively, after aging for 1-2 hr filtering
the solution under vacuum and washing the residue until no
SO4.sup.2- detection, further washing the filter cake with
anhydrous ethanol for several times and then drying it at
100.degree. C., finally calcining the product at 400-700.degree. C.
for 2-4 hr to obtain solid heteropoly acid
SiO.sub.2--Al.sub.2O.sub.3 or SiO.sub.2--MgO.
[0024] Herein carried out calcination is to remove unnecessary
components such as sulfate radicals and nitrate radicals and to
decompose and activate the salt into metallic oxide, which has been
well controlled to avoid the evaporation of SiO.sub.2 under high
temperature and the invalidation of decomposition and activation
under low temperature.
[0025] The following preferred technology program is presented to
give a detailed description for this invention.
[0026] In the preparing method of the fully dull polyester drawn
yarns hereinabove, for the preparation of doped
Bi.sub.2O.sub.3,
[0027] wherein said Ca.sup.2+ solution is an aqueous one with a
concentration of 2-3%, in which the anion is NO.sub.3.sup.-;
wherein said Bi.sup.3+ solution is a product of dissolving 20-25 wt
% of Bi.sub.2O.sub.3 in nitric acid; wherein said precipitant is
ammonia water with a concentration of 2 mol/L; wherein said evenly
mixed solution has a 5-8:100 of molar ratio of Ca.sup.2+ respective
to Bi.sup.3+ before precipitation (The oxygen reduction is
accelerated by introducing Ca.sup.2+ ions into the main catalyst
Bi.sub.2O.sub.3 to increase the conduction rate of oxygen ions in
the polyester, hence if the ion molar ratio is too high the
performance of Bi.sub.2O.sub.3 will be affected whereas if the ion
molar ratio is too small the oxygen ion conduction rate cannot be
improved obviously.);
[0028] wherein said precipitate calcining is preceded by a washing
and drying process, and the drying is carried out under a
temperature of 105-110.degree. C. for 2-3 hr; wherein said
calcining includes steps of a 400.degree. C. heating for 2-3 hr, a
700.degree. C. heating for 1-2 hr, a cooling in air and a grinding
to obtain particles with an average size less than 0.5 micron (In
this invention calcination is a process of importing calcium atom
into the crystal lattice of Bi.sub.2O.sub.3 to form more defects in
the catalyst phase and make them highly dispersed in the surface of
solid solution, so as to destroy the crystal plane structure of
Bi.sub.2O.sub.3. If the cooling rate of calcined precipitate is too
slow, calcium oxide or bismuth oxide tends to crystallize
independently, which will weaken the destruction of crystal plane,
however a cooling in air is conductive to the formation of crystals
while not to the destruction of crystal plane.).
[0029] In the preparing method of the fully dull polyester drawn
yarns hereinabove, for the preparation of multiphase solid acid
base,
[0030] wherein said calcining is a high temperature treatment for
2-4 hr; where n said grinding is to obtain particles with an
average size less than 0.5 micron; wherein said
SiO.sub.2--Al.sub.2O.sub.3 or SiO.sub.2--MgO powder has a SiO.sub.2
content of 20-60 wt % and the purpose of this optimization is to
ensure the synergistic effect of the solid acid base.
[0031] In the preparing method of the fully dull polyester drawn
yarns hereinabove, wherein said 2,5,6,6-tetramethyl-2,5-heptanediol
is synthesized by means of:
[0032] (1) mixing KOH, 3-methyl-3-hydroxybutyne,
3,3-dimethyl-2-butanone and isopropyl ether in the molar ratio of
1-1.2:1:1.2-1.3:2.0-3.0, then carrying out the reaction in an ice
bath for 2-4 hr, finally obtaining octyne diol through a series of
processes of cooling crystallization, centrifugation, washing,
refining and drying;
[0033] (2) mixing octyne diol, alcohol and Pd catalyst in the
weight ratio of 2-3:10:0.01-0.03, then carrying out the reaction
accompanied with a continuous hydrogen input at 40-50.degree. C.
for 50-60 min, finally obtaining
2,5,6,6-tetramethyl-2,5-heptanediol through a series of processes
of separation and purification.
[0034] In the preparing method of the fully dull polyester drawn
yarns hereinabove, wherein said modified polyester is prepared by
means of:
[0035] (1) Esterification
[0036] concocting terephthalic acid, ethylene glycol,
2,5,6,6-tetramethyl-2,5-heptanediol and fluorinated dicarboxylic
acid into a slurry, then adding in the calcined multiphase solid
acid base, the doped Bi.sub.2O.sub.3, the catalyst, the matting
agent and the stabilizer and carrying out the esterification in a
nitrogen atmosphere with a pressure of normal value-0.3 MPa at
250-260.degree. C., finally ending the reaction when the water
distillation reaching more than 90% of the theoretical value;
[0037] (2) Polycondensation
[0038] for the esterification products, smoothly reducing the
pressure to less than 500 Pa (absolute value) within 30-50 min and
carrying out reaction at 250-260.degree. C. for 30-50 min,
successively, further reducing the pressure to less than 100 Pa
(absolute value) and continuing the reaction at 270-282.degree. C.
for 50-90 min.
[0039] In the preparing method of fully dull polyester drawn yarns
hereinabove, the molar ration of terephthalic acid and ethylene
glycol is 1:1.2-2.0, and being relative to the amount of
terephthalic acid, the total addition of
2,5,6,6-tetramethyl-2,5-heptanediol and fluorinated dicarboxylic
acid is 3-5 mol % in a molar ratio of 2-3:3-4, while the addition
of the calcined multiphase solid acid base, the doped
Bi.sub.2O.sub.3, the catalyst, the matting agent and the stabilizer
are 0.03-0.05 wt %, 0.04-0.07 wt %, 0.03-0.05 wt %, 2-3 wt % and
0.01-0.05 wt %, respectively. The additive amounts of
2,5,6,6-tetramethyl-2,5-heptanediol, the fluorinated dicarboxylic
acid, the doped Bi.sub.2O.sub.3 and the calcined multiphase solid
acid base have been optimized to improve the degradation
performance of the fiber without mechanical strength and
crystallinity loss, which could be adjusted according to the actual
application but the adjustment range should not be too large,
otherwise, under the upper overflow the mechanical and
crystallization performance will be effect owing to the destruction
of polyester chain regularity whereas under the lower overflow the
modification cannot be fully achieved.
[0040] In the preparing method of fully dull polyester drawn yarns
mentioned above,
[0041] wherein said catalyst is one of antimony trioxide, ethylene
glycol antimony or antimony acetate, wherein said matting agent is
titanium dioxide, and wherein said stabilizer is triphenyl
phosphate, trimethyl phosphate or trimethyl phosphite;
[0042] wherein said modified polyester has a molecular weight of
25000-30000 and a molecular weight distribution index of
1.8-2.2;
[0043] wherein said FDY technique includes steps of metering,
spinneret extruding, cooling, oiling, stretching, heat setting and
winding;
[0044] wherein said FDY process involves the technological
parameters of spinning temperature 285-295.degree. C., cooling
temperature 20-25.degree. C., interlacing pressure 0.20-0.30 MPa,
godet roller 1 speed 1600-1800 m/min, godet roller 1 temperature
70-80.degree. C., godet roller 2 speed 3000-3200 m/min, godet
roller 2 temperature 105-130.degree. C., winding speed 2950-3130
m/min.
[0045] In the present invention the fully dull polyester drawn yarn
obtained through the preparing method hereinabove is also provided,
which is a type of modified polyester FDY;
[0046] wherein said modified polyester has a molecular chain
structure composed of terephthalic acid segments, ethylene glycol
segments, 2,5,6,6-tetramethyl-2,5-heptanediol segments and
fluorinated dicarboxylic acid segments;
[0047] wherein said modified polyester is also dispersed with the
matting agent, the doped Bi.sub.2O.sub.3 powder and the calcined
multiphase solid acid base powder, and the content of matting agent
is equal to or larger than 2 wt %.
[0048] Prepared through the preferred technology program mentioned
above,
[0049] herein obtained fully dull polyester drawn yarn has the
following performance indices: monofilament fineness 1.0-3.0 dtex,
breaking strength .gtoreq.2.0 cN/dtex, elongation at break
42.0.+-.4.0%, interlacing degree 19.+-.4/m, linear density
deviation rate .ltoreq.1.0%, breaking strength CV value
.ltoreq.8.0%, breaking elongation CV value .ltoreq.0.0%, and
boiling water shrinkage rate 50.0.+-.10.5% (which are close to
those of the common polyester fiber from the existed techniques and
show no obvious decays, moreover, the effect of multiphase solid
acid base is of slow-release and can promise the fiber enough
strength in 3-5 years under the addition mentioned above).
[0050] herein obtained fully dull polyester drawn yarn has an
intrinsic viscosity drop of 18-25% after a storage at 25.degree. C.
and R.H. 65% for 60 months (the corresponding drop of the contrast
sample is just 5%, implying the modification can significantly
accelerate the natural degradation rate of PET fiber and be
favorable to the fiber recycling).
[0051] The mechanism of this invention could be described as
follows.
[0052] In the present invention, the natural degradation
performance of fully dull polyester yarn is improved by the
incorporation of comonomer 2,5,6,6-tetramethyl-2,5-heptanediol, as
well as the fluorinated dicarboxylic acid, the doped
Bi.sub.2O.sub.3 and the calcined multiphase solid acid base,
effectively solving the problem of polyester fiber recycling.
[0053] Firstly, the influence of comonomer
2,5,6,6-tetramethyl-2,5-heptanediol on the natural degradation
performance of PET fiber is interpreted as follows.
[0054] As a matter of fact, the accumulation of macromolecular
chains in polymer are not so compact that there still exist some
gaps between those chains, which are known as the free volumes.
Enough free volumes are necessary for small molecules to diffuse
and penetrate into the polymer, and within certain range, the
larger the free volume, the better the diffusivity and the higher
the permeability. The free volume can be classified by void one and
slit one, and the void free volume is more efficient for the
penetration of small molecules. The size and class of free volume
are dependent on the polymer structures such as steric hindrance,
side group size and side group structure, etc. When a certain site
in polymer main chain is substituted by a side group, the mobility
of the main chain will be changed, as a result, the interaction
force and the distance between polymer chains, as well as the
cohesive energy and the free volume of polymer, will vary
accordingly. In fact, the polarity, the size and length of side
substitution group can draw influences on the rigid, the molecular
interaction, and even the free volume of polymer. Therefore,
different side groups will lead to different penetration
performance.
[0055] The backbone conformation of the straight-chain diols, such
as ethylene glycol and 1,4-butanediol, is like a zigzag almost
lying in a plane. When a H atom of one certain methylene group in
the main chain is substituted by a methyl group, the side C atom
will locate at one vertex of the tetrahedron formed by the sp3
hybridization of the connected main chain C atom. Meanwhile, the
side C atom itself is of sp3 hybridization to form another
tetrahedron, therefore, the methyl substitution group cannot lie in
the zigzag plane. Furthermore, if the H atoms in methyl group are
further substituted by other methyl groups to from a tert-butyl
group more such tetrahedrons will be formed. Hence it is easy to
understand the tert-butyl substituted polyester will possess a
complicated molecular conformation different far from the zigzag to
ensure much more void free volumes. However, if a long side chain
instead of methyl group is bonded to the polyester backbone, the
increase of free volume will be mainly owing to the slit one which
is not so sufficient to promote the penetration. Moreover, the long
alkyl side chain is easy to cause entanglement because of its
flexibility, which is also make against the increase of free
volume.
[0056] In the present invention, the natural degradation
performance of fully dull polyester yarn is improved by introducing
2,5,6,6-tetramethyl-2,5-heptanediol as a comonomer. The existence
of 2,5,6,6-tetramethyl-2,5-heptanediol in PET will change the
mobility of the main chain so as to change the interaction force
and the distance between PET molecular chains, finally enlarging
the void free volumes of PET. Compared with short substitution
chains such as methyl or ethyl group, the tert-butyl group has a
larger space occupation which can gain larger free volume in the
molecular aggregate. Whereas compared with long substitution
chains, the tert-butyl group will mainly provide the void free
volume with larger size than that of the slit free volume which
generated mainly by the long side chains, furthermore, the
tert-butyl group, with a higher rigidity prior to the long alkyl
chains, will seldom cause the entanglement of polymer chains. The
enlargement of void free volume favorable to the penetration of
water or air molecules into the fiber will increase the reactant
concentrations involved in the nucleophilic addition in the
hydrolysis of PET, so as to improve the degradation to a certain
extent.
[0057] Secondly, the influences of the doped Bi.sub.2O.sub.3 and
the calcined multiphase solid acid base on the natural degradation
performance of PET fiber is interpreted as follows.
[0058] The hydrolysis of polyester in alkaline medium is a
nucleophilic addition-elimination process. During the ester
hydrolysis, the nucleophilic addition reaction will occur firstly,
in which OH.sup.- attacks C atom in ester carbonyl RCOOR' to form a
tetrahedral anion intermediate. From this tetrahedral anion,
carboxylic acid RCOOH will be formed by eliminating OR' through the
broken of ester bond, meanwhile alcohol R'OH can also be obtained
from the combination of OR' with H.sup.+. However, normally the
tetrahedral intermediate has a cramped structure with high steric
hindrance, which is detrimental to the nucleophilic addition
reaction, hence the ester hydrolysis usually carries on with a
rather slow rate. In the present invention, the polyester
hydrolysis is significantly accelerated by importing special
structural fluorinated dicarboxylic acid, concretely, dicarboxylic
acid containing a .alpha.-C bonded with fluorine atoms. During the
hydrolysis process of polyester, the electron cloud density in the
C--O bond is reduced by the electron-withdrawing effect of fluorine
atom boned to the .alpha.-C hence the stability of the tetrahedral
anion intermediate will decrease, which is conducive to the
nucleophilic addition reaction. Moreover, the steric hindrance of
fluorinated dicarboxylic acid is less than that of terephthalic
acid, which further promotes the nucleophilic addition reaction,
thus significantly increasing the degradation rate. However, the
degradation rate of polyester will not be improved significantly if
the imported diol contains fluorine atom bonded to .beta.-C because
the electron-withdrawing effect generated by fluorine atom can only
pass to adjacent carbon atom but hardly to C--O bond in ester
group, hence the attacking of OH-- upon carbonyl in nucleophilic
addition reaction will not be affected so much.
[0059] Moreover, normally the polyester fiber in service will be
exposed to the air for a long time. When the polyester contains a
certain amount of oxygen reduction catalyst, the oxygen in air can
penetration into the polyester through the free volume and will be
absorbed and enriched in the surface of oxygen reduction catalyst,
then the absorbed oxygen could be partially reduced to peroxide
which can combine with ester groups to form RCOOOR'. When the
latter further combines with a proton and the O--O bond breaks off,
one RCOOH will form through this broken of ester bond, at the same
time, OR' can connect with H.sup.+ to produce alcohol HOR'. Through
the mechanism mentioned above, the degradation of polyester can be
accelerated.
[0060] The doping of bismuth oxide together with calcium oxide is
realized in this invention via a technological process of solution
blending, precipitation and calcining, so as to change the bismuth
oxide catalyzed oxygen reduction behavior, through which the
degradation rate of polyester is improved. To a certain extent, the
closer the dopant ion radius is to the doped ion radius, the easier
the formation of oxygen vacancies could be, which is favorable to
the conduction of oxygen ions. In this invention, Ca.sup.2+, with
the same radius to Bi.sup.3+ (both are 0.103 nm), is selected as
the doping ion, which can improve the conduction rate of oxygen
ions and the degree of oxygen reduction reaction. The effect of
doping modification on bismuth trioxide is clarified as
follows.
[0061] On one hand, the doping mode herein will destroy the crystal
plane structure of Bi.sub.2O.sub.3 so as to enlarge its specific
surface area, hence the oxygen adsorption capacity per unit mass of
Bi.sub.2O.sub.3 is increased. On the other hand, the doping mode
herein will change the adsorption mode and oxygen reduction
mechanism of Bi.sub.2O.sub.3. Concretely, O.sub.2 molecules tend to
be adsorbed in the end type through a physical adsorption of low
strength or a weak chemical adsorption into the surface of original
monoclinic Bi.sub.2O.sub.3 and to be reduced to peroxides, in
addition, the adsorption will also be affected by the steric
hindrance of Bi atom in the surface. Whereas in the doped
Bi.sub.2O.sub.3, the adsorption changes to the side type which will
not be affect by the steric hindrance, and the proportion of
chemical adsorption is improved, moreover, the breaking off of O--O
bond is also promoted, i.e., the oxygen reduction efficiency is
increased. Therefore, the degradation of polyester rate will be
accelerated by importing doped Bi.sub.2O.sub.3. Nevertheless,
combining bismuth oxide with calcium oxide just by physical
blending cannot lead to the effects mentioned above, because the
crystal plane structure, the adsorption mode and the oxygen
reduction mechanism of Bi.sub.2O.sub.3 will not change in that way.
The degradation will start in the surface of fiber made of common
polyester, whereas in this invention, a comprehensive degradation
with high efficiency could be realized owing to the polyester
dispersed with oxygen reduction agent which can maintain oxygen
internally for a long time.
[0062] Additively, the multiphase solid acid base
SiO.sub.2--Al.sub.2O or SiO.sub.2--MgO, is prepared from the
mixture of silica powder, water, sodium hydroxide and aluminum
sulfate or magnesium sulfate through a high-temperature calcining
at 400-700.degree. C. The purpose of calcination is to remove
unnecessary components such as sulfate radicals and nitrate
radicals and to decompose and activate the salt into metallic
oxide, which should be well controlled to avoid the evaporation of
SiO.sub.2 under high temperature and the invalidation of
decomposition and activation under low temperature.
[0063] Hydrolysis of polyester, the reversal reaction of
esterification, essentially is the fracture process of acyl oxygen
bond in ester group, which includes the nucleophilic addition of
nucleophilic reagent onto carbonyl group to form a tetrahedral
intermediate and the elimination of an anion from it. The
hydrolysis of common polyester is rather slow, and one reason is
H.sub.2O can just act as a weak nucleophilic attacker while the
other is in polyester the carbonyl C atom will show very low
nucleophilic receptor capacity except for being attacked by strong
nucleophilic reagent because it is surrounded by electron donating
groups.
[0064] In the present invention a multiphase solid acid base is
incorporated to accelerate the degradation speed of polyester. On
one hand, solid base can combine with water to produce OH.sup.- ion
with stronger nucleophilic capacity than H.sub.2O, on the other
hand, solid acid can decompose to release H.sup.+ ion which can
protonate the carboxyl oxygen and make it easy to be attacked by a
nucleophilic agent with weak alkalinity such as H.sub.2O.
Accordingly, the problem in the common hydrolysis process of
polyester without the modification, such as the weak nucleophilic
capacity of water and the low polarity of carboxyl oxygen, could be
solved by this acid-base synergistic effect.
[0065] In a carboxyl group, the lone pair electrons in hydroxyl O
atom will be delocalized via conjugating with the .pi. electron of
carbonyl group, which will weaken the hydroxyl bond and result in
the decomposition of carboxyl group into an anion and a proton.
Therefore, normally the end carboxyl group in common polyester is
the start of hydrolysis because the released proton will catalyze
the nucleophilic addition. More end carboxyl group will be formed
from the hydrolysis broken of polyester chain and the hydrolysis
can be enhanced by the incorporation of solid acid base just as
mentioned above, and so on. Therefore, the addition of solid acid
base can efficiently accelerate the natural degradation of
polyester.
[0066] In conclusion, the present invention provides
[0067] (1) a type of fully dull polyester drawn yarns with improved
recovery performance for good application prospect without quality
decay;
[0068] (2) a method for preparing the fully dull polyester drawn
yarns in which the natural degradation performance of fiber is
improved by introducing 2,5,6,6-tetramethyl-2,5-heptanediol, the
fluorinated dicarboxylic acid, the doped Bi.sub.2O.sub.3 and the
calcined multiphase solid acid base as modifiers.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0069] Based on above mentioned method, the following embodiments
are carried out for further demonstration in the present invention.
It is to be understood that these embodiments are only intended to
illustrate the invention and are not intended to limit the scope of
the invention. In addition, it should be understood that after
reading the contents described in the present invention, those
technical personnel in this field can make various changes or
modifications to the invention, and these equivalent forms also
fall within the scope of the claims attached to the
application.
Example 1
[0070] A method for preparing the fully dull polyester drawn yarns,
comprising the steps:
[0071] (1) Preparation of modified polyester
[0072] (1.1) Preparation of multiphase solid acid base
SiO.sub.2--Al.sub.2O.sub.3
[0073] adding 4 wt % of disperser PEG 6000 into a sodium silicate
solution with an SiO.sub.2 equivalent concentration of 12 wt % and
stirring the mixture at 45.degree. C. till be soluble, then evenly
adding in 12 wt % of sulfuric acid solution till pH=10, after aging
for 1.0 hr continuing to add in sulfuric acid solution till pH=8,
heating the solution to 95.degree. C. and aging for 2 hr, then
filtering the solution under vacuum and washing the residue with
water until no SO4.sup.2- detection then further washing with
anhydrous ethanol for several times, finally drying the product at
80.degree. C. and grinding it to obtain silica powder;
[0074] adding 1 part of above silica powder into 55 parts of water
and stirring to disperse, then dripping in 2 parts of aluminum
sulfate solution with a weight concentration of 4.5%, adjusting the
pH value firstly to neutral and then to 8 with 0.5 mol/L sodium
hydroxide solution and 8% sulfuric acid successively, after aging
for 2 hr filtering the solution under vacuum and washing the
residue until no SO4.sup.2- detection, further washing the filter
cake with anhydrous ethanol for several times and then drying it at
100.degree. C., finally calcining the product at 500.degree. C. for
3 hr to obtain solid acid base SiO.sub.2--Al.sub.2O.sub.3 with an
average size of 0.4 micron and a silica content of 40 wt %;
[0075] (1.2) Doping modification of Bi.sub.2O.sub.3
[0076] (1.2.1) evenly mixing a 2.5 wt % of Ca(NO.sub.3).sub.2
aqueous solution and a 22 wt % of Bi.sub.2O.sub.3 nitric acid
solution in 7:100 molar ratio of Ca.sup.2+ and Bi.sup.3+;
[0077] (1.2.2) depositing the mixed solution by adding 2 mol/L of
ammonia water till pH=10, then washing and drying (105.degree. C.,
2.5 hr) the precipitate;
[0078] (1.2.3) after the treatment composed of a heating at
400.degree. C. for 2.5 hr, a heating at 700.degree. C. for 1.5 hr
and a cooling in air, crushing the precipitate to doped
Bi.sub.2O.sub.3 powder with an average size of 0.45 micron;
[0079] (1.3) Synthesizing 2,5,6,6-tetramethyl-2,5-heptanediol
[0080] (1.3.1) mixing KOH, 3-methyl-3-hydroxybutyne,
3,3-dimethyl-2-butanone and isopropyl ether in the molar ratio of
1:1:1.2:2.0, then carrying out the reaction in an ice bath for 2
hr, finally obtaining octyne diol through a series of processes of
cooling crystallization, centrifugation, washing, refining and
drying;
[0081] (1.3.2) mixing octyne diol, alcohol and Pd catalyst in the
weight ratio of 2:10:0.01, then carrying out the reaction
accompanied with a continuous hydrogen input at 40.degree. C. for
50 min, finally obtaining 2,5,6,6-tetramethyl-2,5-heptanediol
through a series of processes of separation and purification;
wherein obtained target compound possessing a molecular structure
just as shown in Formula I;
##STR00002##
[0082] (1.4) Esterification
[0083] concocting terephthalic acid, ethylene glycol,
2,5,6,6-tetramethyl-2,5-heptanediol and 2,2-difluoro-1,3-malonic
acid into a slurry, then adding in multiphase solid acid base
SiO.sub.2--Al.sub.2O.sub.3, doped Bi.sub.2O.sub.3, antimony
trioxide, titanium dioxide and triphenyl phosphate and carrying out
the esterification in a nitrogen atmosphere with a pressure of 0.3
MPa at 250.degree. C., finally ending the reaction when the water
distillation reaching 90.1% of the theoretical value, wherein the
molar ration of terephthalic acid and ethylene glycol is 1:1.2, and
being relative to the amount of terephthalic acid, the total
addition of 2,5,6,6-tetramethyl-2,5-heptanediol and
2,2-difluoro-1,3-malonic acid is 3 mol % in a molar ratio of 2:3,
while the addition of multiphase solid acid base
SiO.sub.2--Al.sub.2O.sub.3, doped Bi.sub.2O.sub.3, antimony
trioxide, titanium dioxide and triphenyl phosphate are 0.03 wt %,
0.04 wt %, 0.03 wt %, 2 wt % and 0.01 wt %, respectively;
[0084] (1.5) Polycondensation
[0085] for the esterification products, smoothly reducing the
pressure to 499 Pa (absolute value) within 30 min and carrying out
reaction at 250.degree. C. for 30 min, successively, further
reducing the pressure to 99 Pa (absolute value) and continuing the
reaction at 270.degree. C. for 50 min, finally obtaining the
modified polyester with a molecular weight of 25000 and a molecular
weight distribution index of 1.8;
[0086] (2) Spinning of Fully Dull Polyester Drawn Yarn
[0087] through a FDY technological way including stages of
metering, spinneret extruding (at 285.degree. C.), cooling (at
20.degree. C.), oiling, stretching as well as heat setting (carried
on with the parameters of interlacing pressure 0.20 MPa, godet
roller 1 speed 1600 m/min, godet roller 1 temperature 70.degree.
C., godet roller 2 speed 3000 m/min, godet roller 2 temperature
105.degree. C.), and winding (2950 m/min), converting the modified
polyester into fully dull polyester drawn yarns.
[0088] Finally obtained fully dull polyester yarn has an intrinsic
viscosity drop of 18% after stored at 25.degree. C. and R.H. 65%
for 60 months, and the other property indices are listed in Table
1.
[0089] Comparison 1
[0090] A method for preparing the fully dull polyester drawn yarns
involved steps basically the same as those in Example 1, except for
no addition of 2,5,6,6-tetramethyl-2,5-heptanediol,
2,2-difluoro-1,3-malonic acid, multiphase solid acid base
SiO.sub.2--Al.sub.2O.sub.3 and doped Bi.sub.2O.sub.3 in step (1),
from which the finally obtained fully dull polyester drawn yarn has
an intrinsic viscosity drop of 4.8% after stored at 25.degree. C.
and R.H. 65% for 60 months, and the other property indices are
listed in Table 1.
[0091] Comparison 2
[0092] A method for preparing the fully dull polyester drawn yarns
involved steps basically the same as those in Example 1, except for
no addition of 2,5,6,6-tetramethyl-2,5-heptanediol in step (1),
from which the finally obtained fully dull polyester drawn yarn has
an intrinsic viscosity drop of 12.6% after stored at 25.degree. C.
and R.H. 65% for 60 months, and the other property indices are
listed in Table 1.
[0093] Comparison 3
[0094] A method for preparing the fully dull polyester drawn yarns
involved steps basically the same as those in Example 1, except for
no addition of 2,2-difluoro-1,3-malonic acid in step (1), from
which the finally obtained fully dull polyester drawn yarn has an
intrinsic viscosity drop of 11.1% after stored at 25.degree. C. and
R.H. 65% for 60 months, and the other property indices are listed
in Table 1.
[0095] Comparison 4
[0096] A method for preparing the fully dull polyester drawn yarns
involved steps basically the same as those in Example 1, except for
no addition of doped Bi.sub.2O.sub.3 in step (1), from which the
finally obtained fully dull polyester drawn yarn has an intrinsic
viscosity drop of 12.7% after stored at 25.degree. C. and R.H. 65%
for 60 months, and the other property indices are listed in Table
1.
[0097] Comparison 5
[0098] A method for preparing the fully dull polyester drawn yarns
involved steps basically the same as those in Example 1, except for
no addition of multiphase solid acid base
SiO.sub.2--Al.sub.2O.sub.3 in step (1), from which the finally
obtained fully dull polyester drawn yarn has an intrinsic viscosity
drop of 13.2% after stored at 25.degree. C. and R.H. 65% for 60
months, and the other property indices are listed in Table 1.
[0099] Based on the comparative analysis between Example 1 and
Comparison 1-5, it could be found that the incorporation of
addition of 2,5,6,6-tetramethyl-2,5-heptanediol,
2,2-difluoro-1,3-malonic acid, multiphase solid acid base
SiO.sub.2--Al.sub.2O.sub.3 and doped Bi.sub.2O.sub.3 will
significantly improve the natural degradation performance of
polyester fiber, in which doped Bi.sub.2O.sub.3 increases the
conductivity of oxygen ion and the oxygen reduction extent,
2,2-difluoro-1,3-malonic acid reduces the electron cloud density of
C--O bond, solid acid base SiO.sub.2--Al.sub.2O.sub.3 releases
nucleophilic ion OH.sup.-, and 2,5,6,6-tetramethyl-2,5-heptanediol
enlarges the free volume favorable to the penetration of air and
wafter. All those effects can promote the nucleophilic addition
involved in polyester hydrolysis and synergistically improve the
degradation polyester without decaying the processibility and
mechanical property of the fiber.
[0100] Comparison 6
[0101] A method for preparing the fully dull polyester drawn yarn
involved steps basically the same as those in Example 1, except for
using 1,2-dodecyl glycol instead of
2,5,6,6-tetramethyl-2,5-heptanediol in step (1), from which the
finally obtained fully dull polyester yarn possesses the mechanical
performance indices of monofilament fineness 2.95 dtex, breaking
strength 2.2 cN/dtex, elongation at break 45.1%, interlacing degree
22/m, linear density deviation rate 0.82%, breaking strength CV
value 6.5%, breaking elongation CV value 10.4%, and boiling water
shrinkage rate 40.5%, as well as an intrinsic viscosity drop of
13.7% after stored at 25.degree. C. and R.H. 65% for 60 months
[0102] The comparison with Example 1 shows that
2,2,5,5-tetramethyl-3,4-hexanediol and
2,5,6,6-tetramethyl-2,5-heptanediol are more efficient than
1,2-dodecyl glycol on improving the dyeing performances of the
wool-like polyester filament, and the reason on one hand is that
the short side chain can enlarge the void free volume whereas the
long side can mainly enlarge the slit free volume, and the void
free volume is more efficient than the slit one for the penetration
of dye particles into the fiber, on the other hand, the short side
chain with higher rigidity will seldom cause the molecular chain
entanglement and gain more free volume in the molecular
aggregate.
Example 2
[0103] A method for preparing the fully dull polyester drawn yarns,
comprising the steps:
[0104] (1) Preparation of modified polyester
[0105] (1.1) Preparation of multiphase solid acid base
SiO.sub.2--MgO
[0106] adding 3 wt % of disperser PEG 6000 into a sodium silicate
solution with an SiO.sub.2 equivalent concentration of 10 wt % and
stirring the mixture at 40.degree. C. till be soluble, then evenly
adding in 10 wt % of sulfuric acid solution till pH=10, after aging
for 0.5 hr continuing to add in sulfuric acid solution till pH=8,
heating the solution to 90.degree. C. and aging for 2 hr, then
filtering the solution under vacuum and washing the residue with
water until no SO4.sup.2- detection then further washing with
anhydrous ethanol for several times, finally drying the product at
80.degree. C. and grinding it to obtain silica powder;
[0107] adding 1 part of above silica powder into 50 parts of water
and stirring to disperse, then dripping in 3 parts of magnesium
sulfate solution with a weight concentration of 4%, adjusting the
pH value firstly to neutral and then to 8 with 0.5 mol/L sodium
hydroxide solution and 8% sulfuric acid successively, after aging
for lhr filtering the solution under vacuum and washing the residue
until no SO4.sup.2- detection, further washing the filter cake with
anhydrous ethanol for several times and then drying it at
100.degree. C., finally calcining the product at 400.degree. C. for
4 hr to obtain solid acid base SiO.sub.2--MgO with an average size
of 0.4 micron and a silica content of 20 wt %;
[0108] (1.2) Doping modification of Bi.sub.2O.sub.3
[0109] (1.2.1) evenly mixing a 2 wt % of Ca(NO.sub.3).sub.2 aqueous
solution and a 20 wt % of Bi.sub.2O.sub.3 nitric acid solution in
5:100 molar ratio of Ca.sup.2+ and Bi.sup.3+;
[0110] (1.2.2) depositing the mixed solution by adding 2 mol/L of
ammonia water till pH=9, then washing and drying (105.degree. C., 2
hr) the precipitate;
[0111] (1.2.3) after the treatment composed of a heating at
400.degree. C. for 2 hr, a heating at 700.degree. C. for 1 hr and a
cooling in air, crushing the precipitate to doped Bi.sub.2O.sub.3
powder with an average size of 0.4 micron;
[0112] (1.3) Synthesizing 2,5,6,6-tetramethyl-2,5-heptanediol
[0113] (1.3.1) mixing KOH, 3-methyl-3-hydroxybutyne,
3,3-dimethyl-2-butanone and isopropyl ether in the molar ratio of
1.1:1:1.2:2.3, then carrying out the reaction in an ice bath for 2
hr, finally obtaining octyne diol through a series of processes of
cooling crystallization, centrifugation, washing, refining and
drying;
[0114] (1.3.2) mixing octyne diol, alcohol and Pd catalyst in the
weight ratio of 2:10:0.01, then carrying out the reaction
accompanied with a continuous hydrogen input at 45.degree. C. for
50 min, finally obtaining 2,5,6,6-tetramethyl-2,5-heptanediol
through a series of processes of separation and purification;
wherein obtained target compound possessing a molecular structure
just as shown in Formula I;
[0115] (1.4) Esterification
[0116] concocting terephthalic acid, ethylene glycol,
2,5,6,6-tetramethyl-2,5-heptanediol and 2,2-difluoro-1,4-succinic
acid into a slurry, then adding in multiphase solid acid base
SiO.sub.2--MgO, doped Bi.sub.2O.sub.3, ethylene glycol antimony,
titanium dioxide and trimethyl phosphate and carrying out the
esterification in a nitrogen atmosphere with a pressure of normal
value at 260.degree. C., finally ending the reaction when the water
distillation reaching 95% of the theoretical value, wherein the
molar ration of terephthalic acid and ethylene glycol is 1:2.0, and
being relative to the amount of terephthalic acid, the total
addition of 2,5,6,6-tetramethyl-2,5-heptanediol and
2,2-difluoro-1,4-succinic acid is 5 mool % in a molar ratio of 3:4,
while the addition of multiphase solid acid base SiO.sub.2--MgO,
doped Bi.sub.2O.sub.3, ethylene glycol antimony, titanium dioxide
and trimethyl phosphate are 0.05 wt %, 0.07 wt %, 0.05 wt %, 3 wt %
and 0.05 wt %, respectively;
[0117] (1.5) Polycondensation
[0118] for the esterification products, smoothly reducing the
pressure to 450 Pa (absolute value) within 50 min and carrying out
reaction at 260.degree. C. for 50 min, successively, further
reducing the pressure to 90 Pa (absolute value) and continuing the
reaction at 282.degree. C. for 90 min, finally obtaining the
modified polyester with a molecular weight of 30000 and a molecular
weight distribution index of 2.2;
[0119] (2) Spinning of fully dull polyester drawn yarn
[0120] through a FDY technological way including stages of
metering, spinneret extruding (at 295.degree. C.), cooling (at
25.degree. C.), oiling, stretching as well as heat setting (carried
on with the parameters of interlacing pressure 0.30 MPa, godet
roller 1 speed 1800 m/min, godet roller 1 temperature 80.degree.
C., godet roller 2 speed 3200 m/min, godet roller 2 temperature
130.degree. C.), and winding (3130 m/min), converting the modified
polyester into fully dull polyester drawn yarns.
[0121] Finally obtained fully dull polyester yarn has an intrinsic
viscosity drop of 25% after stored at 25.degree. C. and R.H. 65%
for 60 months, and the other property indices are listed in Table
1.
Example 3
[0122] A method for preparing the fully dull polyester drawn yarns,
comprising the steps:
[0123] (1) Preparation of modified polyester
[0124] (1.1) Preparation of multiphase solid acid base
SiO.sub.2--Al.sub.2O.sub.3
[0125] adding 3 wt % of disperser PEG 6000 into a sodium silicate
solution with an SiO.sub.2 equivalent concentration of 10 wt % and
stirring the mixture at 40.degree. C. till be soluble, then evenly
adding in 10 wt % of sulfuric acid solution till pH=10, after aging
for 0.5 hr continuing to add in sulfuric acid solution till pH=8,
heating the solution to 90.degree. C. and aging for 2 hr, then
filtering the solution under vacuum and washing the residue with
water until no SO4.sup.2- detection then further washing with
anhydrous ethanol for several times, finally drying the product at
85.degree. C. and grinding it to obtain silica powder;
[0126] adding 1 part of above silica powder into 60 parts of water
and stirring to disperse, then dripping in 2 parts of aluminum
sulfate solution with a weight concentration of 4%, adjusting the
pH value firstly to neutral and then to 8 with 1.0 mol/L sodium
hydroxide solution and 10% sulfuric acid successively, after aging
for 2 hr filtering the solution under vacuum and washing the
residue until no SO4.sup.2- detection, further washing the filter
cake with anhydrous ethanol for several times and then drying it at
100.degree. C., finally calcining the product at 700.degree. C. for
2 hr to obtain solid acid base SiO.sub.2--Al.sub.2O.sub.3 with an
average size of 0.4 micron and a silica content of 60 wt %;
[0127] (1.2) Doping modification of Bi.sub.2O.sub.3
[0128] (1.2.1) evenly mixing a 3 wt % of Ca(NO.sub.3).sub.2 aqueous
solution and a 25 wt % of Bi.sub.2O.sub.3 nitric acid solution in
8:100 molar ratio of Ca.sup.2+ and Bi.sup.3+;
[0129] (1.2.2) depositing the mixed solution by adding 2 mol/L of
ammonia water till pH=9, then washing and drying (110.degree. C., 3
hr) the precipitate;
[0130] (1.2.3) after the treatment composed of a heating at
400.degree. C. for 3 hr, a heating at 700.degree. C. for 2 hr and a
cooling in air, crushing the precipitate to doped Bi.sub.2O.sub.3
powder with an average size of 0.4 micron;
[0131] (1.3) Synthesizing 2,5,6,6-tetramethyl-2,5-heptanediol
[0132] (1.3.1) mixing KOH, 3-methyl-3-hydroxybutyne,
3,3-dimethyl-2-butanone and isopropyl ether in the molar ratio of
1.2:1:1.25:2.0, then carrying out the reaction in an ice bath for 3
hr, finally obtaining octyne diol through a series of processes of
cooling crystallization, centrifugation, washing, refining and
drying;
[0133] (1.3.2) mixing octyne diol, alcohol and Pd catalyst in the
weight ratio of 3:10:0.03, then carrying out the reaction
accompanied with a continuous hydrogen input at 40.degree. C. for
50 min, finally obtaining 2,5,6,6-tetramethyl-2,5-heptanediol
through a series of processes of separation and purification;
wherein obtained target compound possessing a molecular structure
just as shown in Formula I;
[0134] (1.4) Esterification
[0135] concocting terephthalic acid, ethylene glycol,
2,5,6,6-tetramethyl-2,5-heptanediol and 2,2-difluoro-1,5-glutaric
acid into a slurry, then adding in multiphase solid acid base
SiO.sub.2--Al.sub.2O.sub.3, doped Bi.sub.2O.sub.3, antimony
acetate, titanium dioxide and trimethyl phosphite and carrying out
the esterification in a nitrogen atmosphere with a pressure of 0.2
MPa at 255.degree. C., finally ending the reaction when the water
distillation reaching 92% of the theoretical value, wherein the
molar ration of terephthalic acid and ethylene glycol is 1:1.6, and
being relative to the amount of terephthalic acid, the total
addition of 2,5,6,6-tetramethyl-2,5-heptanediol and
2,2-difluoro-1,5-glutaric acid is 4 mol % in a molar ratio of 2:4,
while the addition of multiphase solid acid base
SiO.sub.2--Al.sub.2O.sub.3, doped Bi.sub.2O.sub.3, antimony
acetate, titanium dioxide and trimethyl phosphite are 0.04 wt %,
0.055 wt %, 0.04 wt %, 2.5 wt % and 0.03 wt %, respectively;
[0136] (1.5) Polycondensation
[0137] for the esterification products, smoothly reducing the
pressure to 480 Pa (absolute value) within 40 min and carrying out
reaction at 255.degree. C. for 40 min, successively, further
reducing the pressure to 95 Pa (absolute value) and continuing the
reaction at 276.degree. C. for 70 min, finally obtaining the
modified polyester with a molecular weight of 27000 and a molecular
weight distribution index of 2.0;
[0138] (2) Spinning of fully dull polyester drawn yarn
[0139] through a FDY technological way including stages of
metering, spinneret extruding (at 290.degree. C.), cooling (at
22.degree. C.), oiling, stretching as well as heat setting (carried
on with the parameters of interlacing pressure 0.25 MPa, godet
roller 1 speed 1700 m/min, godet roller 1 temperature 75.degree.
C., godet roller 2 speed 3100 m/min, godet roller 2 temperature
118.degree. C.), and winding (3030 m/min), converting the modified
polyester into fully dull polyester drawn yarns.
[0140] Finally obtained fully dull polyester yarn has an intrinsic
viscosity drop of 21% after stored at 25.degree. C. and R.H. 65%
for 60 months, and the other property indices are listed in Table
1.
Example 4
[0141] A method for preparing the fully dull polyester drawn yarns,
comprising the steps:
[0142] (1) Preparation of modified polyester
[0143] (1.1) Preparation of multiphase solid acid base
SiO.sub.2--MgO
[0144] adding 4 wt % of disperser PEG 6000 into a sodium silicate
solution with an SiO.sub.2 equivalent concentration of 14 wt % and
stirring the mixture at 45.degree. C. till be soluble, then evenly
adding in 13 wt % of sulfuric acid solution till pH=10, after aging
for 1.0 hr continuing to add in sulfuric acid solution till pH=8,
heating the solution to 95.degree. C. and aging for 2 hr, then
filtering the solution under vacuum and washing the residue with
water until no SO4.sup.2- detection then further washing with
anhydrous ethanol for several times, finally drying the product at
85.degree. C. and grinding it to obtain silica powder;
[0145] adding 1 part of above silica powder into 57 parts of water
and stirring to disperse, then dripping in 2 parts of magnesium
sulfate solution with a weight concentration of 4%, adjusting the
pH value firstly to neutral and then to 8 with 0.8 mol/L sodium
hydroxide solution and 9% sulfuric acid successively, after aging
for 1.5 hr filtering the solution under vacuum and washing the
residue until no SO4.sup.2- detection, further washing the filter
cake with anhydrous ethanol for several times and then drying it at
100.degree. C., finally calcining the product at 600.degree. C. for
4 hr to obtain solid acid base SiO.sub.2--MgO with an average size
of 0.4 micron and a silica content of 45 wt %;
[0146] (1.2) Doping modification of Bi.sub.2O.sub.3
[0147] (1.2.1) evenly mixing a 2.5 wt % of Ca(NO.sub.3).sub.2
aqueous solution and a 25 wt % of Bi.sub.2O.sub.3 nitric acid
solution in 8:100 molar ratio of Ca.sup.2+ and Bi.sup.3+;
[0148] (1.2.2) depositing the mixed solution by adding 2 mol/L of
ammonia water till pH=10, then washing and drying (110.degree. C.,
3 hr) the precipitate;
[0149] (1.2.3) after the treatment composed of a heating at
400.degree. C. for 2.5 hr, a heating at 700.degree. C. for 2 hr and
a cooling in air, crushing the precipitate to doped Bi.sub.2O.sub.3
powder with an average size of 0.4 micron;
[0150] (1.3) Synthesizing 2,5,6,6-tetramethyl-2,5-heptanediol
[0151] (1.3.1) mixing KOH, 3-methyl-3-hydroxybutyne,
3,3-dimethyl-2-butanone and isopropyl ether in the molar ratio of
1.2:1:1.3:2.5, then carrying out the reaction in an ice bath for 3
hr, finally obtaining octyne diol through a series of processes of
cooling crystallization, centrifugation, washing, refining and
drying;
[0152] (1.3.2) mixing octyne diol, alcohol and Pd catalyst in the
weight ratio of 2.5:10:0.02 then carrying out the reaction
accompanied with a continuous hydrogen input at 45.degree. C. for
60 min, finally obtaining 2,5,6,6-tetramethyl-2,5-heptanediol
through a series of processes of separation and purification;
wherein obtained target compound possessing a molecular structure
just as shown in Formula I;
[0153] (1.4) Esterification
[0154] concocting terephthalic acid, ethylene glycol,
2,5,6,6-tetramethyl-2,5-heptanediol and
2,2,3,3-tetrafluoro-1,4-succinic acid into a slurry, then adding in
multiphase solid acid base SiO.sub.2--MgO, doped Bi.sub.2O.sub.3,
ethylene glycol antimony, titanium dioxide and triphenyl phosphate
and carrying out the esterification in a nitrogen atmosphere with a
pressure of 0.25 MPa at 250.degree. C., finally ending the reaction
when the water distillation reaching 94% of the theoretical value,
wherein the molar ration of terephthalic acid and ethylene glycol
is 1:1.9, and being relative to the amount of terephthalic acid,
the total addition of 2,5,6,6-tetramethyl-2,5-heptanediol and
2,2,3,3-tetrafluoro-1,4-succinic acid is 5 mol % in a molar ratio
of 2.5:3.5, while the addition of multiphase solid acid base
SiO.sub.2--MgO, doped Bi.sub.2O.sub.3, ethylene glycol antimony,
titanium dioxide and triphenyl phosphate are 0.03 wt %, 0.04 wt %,
0.03 wt %, 2 wt % and 0.05 wt %, respectively;
[0155] (1.5) Polycondensation
[0156] for the esterification products, smoothly reducing the
pressure to 480 Pa (absolute value) within 35 min and carrying out
reaction at 258.degree. C. for 45 min, successively, further
reducing the pressure to 96 Pa (absolute value) and continuing the
reaction at 270.degree. C. for 55 min, finally obtaining the
modified polyester with a molecular weight of 26000 and a molecular
weight distribution index of 1.9;
[0157] (2) Spinning of fully dull polyester drawn yarn
[0158] through a FDY technological way including stages of
metering, spinneret extruding (at 285.degree. C.), cooling (at
25.degree. C.), oiling, stretching as well as heat setting (carried
on with the parameters of interlacing pressure 0.25 MPa, godet
roller 1 speed 1800 m/min, godet roller 1 temperature 75.degree.
C., godet roller 2 speed 3100 m/min, godet roller 2 temperature
105.degree. C.), and winding (2950 m/min), converting the modified
polyester into fully dull polyester drawn yarns.
[0159] Finally obtained fully dull polyester yarn has an intrinsic
viscosity drop of 18% after stored at 25.degree. C. and R.H. 65%
for 60 months, and the other property indices are listed in Table
1.
Example 5
[0160] A method for preparing the fully dull polyester drawn yarns,
comprising the steps:
[0161] (1) Preparation of modified polyester
[0162] (1.1) Preparation of multiphase solid acid base
SiO.sub.2--MgO
[0163] adding 5 wt % of disperser PEG 6000 into a sodium silicate
solution with an SiO.sub.2 equivalent concentration of 15wt% and
stirring the mixture at 45.degree. C. till be soluble, then evenly
adding in 10 wt % of sulfuric acid solution till pH=10, after aging
for 1.0 hr continuing to add in sulfuric acid solution till pH=8,
heating the solution to 95.degree. C. and aging for 2 hr, then
filtering the solution under vacuum and washing the residue with
water until no SO4.sup.2- detection then further washing with
anhydrous ethanol for several times, finally drying the product at
85.degree. C. and grinding it to obtain silica powder;
[0164] adding 1 part of above silica powder into 59 parts of water
and stirring to disperse, then dripping in 2 parts of magnesium
sulfate solution with a weight concentration of 4%, adjusting the
pH value firstly to neutral and then to 8 with 0.7 mol/L sodium
hydroxide solution and 10% sulfuric acid successively, after aging
for 2 hr filtering the solution under vacuum and washing the
residue until no SO4.sup.2- detection, further washing the filter
cake with anhydrous ethanol for several times and then drying it at
100.degree. C., finally calcining the product at 650.degree. C. for
3.5 hr to obtain solid acid base SiO.sub.2--MgO with an average
size of 0.45 micron and a silica content of 51 wt %;
[0165] (1.2) Doping modification of Bi.sub.2O.sub.3
[0166] (1.2.1) evenly mixing a 2.5 wt % of Ca(NO.sub.3).sub.2
aqueous solution and a 24 wt % of Bi.sub.2O.sub.3 nitric acid
solution in 6:100 molar ratio of Ca.sup.2+ and Bi.sup.3+;
[0167] (1.2.2) depositing the mixed solution by adding 2 mol/L of
ammonia water till pH=10, then washing and drying (107.degree. C.,
2.5 hr) the precipitate;
[0168] (1.2.3) after the treatment composed of a heating at
400.degree. C. for 2.5 hr, a heating at 700.degree. C. for 2 hr and
a cooling in air, crushing the precipitate to doped Bi.sub.2O.sub.3
powder with an average size of 0.45 micron;
[0169] (1.3) Synthesizing 2,5,6,6-tetramethyl-2,5-heptanediol
[0170] (1.3.1) mixing KOH, 3-methyl-3-hydroxybutyne,
3,3-dimethyl-2-butanone and isopropyl ether in the molar ratio of
1:1:1.3:3.0, then carrying out the reaction in an ice bath for 4
hr, finally obtaining octyne diol through a series of processes of
cooling crystallization, centrifugation, washing, refining and
drying;
[0171] (1.3.2) mixing octyne diol, alcohol and Pd catalyst in the
weight ratio of 2.5:10:0.02 then carrying out the reaction
accompanied with a continuous hydrogen input at 50.degree. C. for
55 min, finally obtaining 2,5,6,6-tetramethyl-2,5-heptanediol
through a series of processes of separation and purification;
wherein obtained target compound possessing a molecular structure
just as shown in Formula I;
[0172] (1.4) Esterification
[0173] concocting terephthalic acid, ethylene glycol,
2,5,6,6-tetramethyl-2,5-heptanediol and 2,2-difluoro-1,3-malonic
acid into a slurry, then adding in multiphase solid acid base
SiO.sub.2--MgO, doped Bi.sub.2O.sub.3, antimony acetate, titanium
dioxide and triphenyl phosphate and carrying out the esterification
in a nitrogen atmosphere with a pressure of 0.15 MPa at 260.degree.
C., finally ending the reaction when the water distillation
reaching 96% of the theoretical value, wherein the molar ration of
terephthalic acid and ethylene glycol is 1:2.0, and being relative
to the amount of terephthalic acid, the total addition of
2,5,6,6-tetramethyl-2,5-heptanediol and 2,2-difluoro-1,3-malonic
acid is 3 mol % in a molar ratio of 2:4, while the addition of
multiphase solid acid base SiO.sub.2--MgO, doped Bi.sub.2O.sub.3,
ethylene glycol antimony, titanium dioxide and triphenyl phosphate
are 0.04 wt %, 0.05 wt %, 0.04 wt %, 3 wt % and 0.04 wt %,
respectively;
[0174] (1.5) Polycondensation
[0175] for the esterification products, smoothly reducing the
pressure to 480 Pa (absolute value) within 50 min and carrying out
reaction at 255.degree. C. for 50 min, successively, further
reducing the pressure to 95 Pa (absolute value) and continuing the
reaction at 282.degree. C. for 80 min, finally obtaining the
modified polyester with a molecular weight of 29000 and a molecular
weight distribution index of 2.1;
[0176] (2) Spinning of fully dull polyester drawn yarn
[0177] through a FDY technological way including stages of
metering, spinneret extruding (at 285.degree. C.), cooling (at
25.degree. C.), oiling, stretching as well as heat setting (carried
on with the parameters of interlacing pressure 0.25 MPa, godet
roller 1 speed 1800 m/min, godet roller 1 temperature 75.degree.
C., godet roller 2 speed 3100 m/min, godet roller 2 temperature
105.degree. C.), and winding (2950 m/min), converting the modified
polyester into fully dull polyester drawn yarns.
[0178] Finally obtained fully dull polyester yarn has an intrinsic
viscosity drop of 18% after stored at 25.degree. C. and R.H. 65%
for 60 months, and the other property indices are listed in Table
1.
Example 6
[0179] A method for preparing the fully dull polyester drawn yarns,
comprising the steps:
[0180] (1) Preparation of modified polyester
[0181] (1.1) Doping modification of Bi.sub.2O.sub.3
[0182] (a) evenly mixing a 3 wt % of Ca(NO.sub.3).sub.2 aqueous
solution and a 24 wt % of Bi.sub.2O.sub.3 nitric acid solution,
maintaining a 7:100 of molar ratio of Ca.sup.2+ and Bi.sup.3+;
[0183] (b) depositing the mixed solution by adding 2 mol/L of
ammonia water until pH value reaches 10, then washing and drying
(110.degree. C., 2.5 hr) the precipitate;
[0184] (c) after the treatment composed of a heating at 400
.degree. C. for 3 hr, a heating at 700.degree. C. for 1.5 hr and a
cooling in air, crushing the precipitate to doped Bi.sub.2O.sub.3
powder with an average size of 0.45 .mu.m;
[0185] (1.2) Esterification
[0186] concocting terephthalic acid, ethylene glycol,
tetramethyldisiloxane diol and 2,2-difluoro-1,4-succinic acid into
a slurry (in which the molar ration of terephthalic acid and
ethylene glycol is 1:2.0, the total addition of
tetramethyldisiloxane diol and 2,2-difluoro-1,4-succinic acid with
a molar ratio of 3:5 is 4.5 mol % relative to the amount of
terephthalic acid), and adding in 0.07 wt % of the doped
Bi.sub.2O.sub.3, 0.04 wt % of antimony trioxide, 0.20 wt % of
titanium dioxide and 0.05 wt % of trimethyl phosphite (all are
relative to the amount of terephthalic acid), then carrying out the
esterification in nitrogen under a normal pressure at 260.degree.
C., finally ending the reaction when the water distillation rate
reaches 91% of the theoretical value;
[0187] (1.3) Polycondensation
[0188] after smoothly reducing the pressure from normal value to
450 Pa within 35 min, conducting the low vacuum polycondensation
for the esterification products at 270.degree. C. for 50 min, then
further reducing the pressure to 100 Pa and continuing the high
vacuum polycondensation at 275.degree. C. for 85 min, finally
obtaining the modified polyester with a molecular weight of 27800
and a molecular weight distribution index of 1.8;
[0189] (2) Spinning of fully dull polyester drawn yarn
[0190] through a FDY technological way including stages of
metering, spinneret extruding (at 295.degree. C.), cooling (at
18.degree. C.), oiling, stretching as well as heat setting (carried
on with the parameters of interlacing pressure 0.20 MPa, godet
roller 1 speed 2300 m/min, godet roller 1 temperature 80.degree.
C., godet roller 2 speed 4400 m/min, godet roller 2 temperature
130.degree. C.), and winding (4420 m/min), converting the modified
polyester into fully dull polyester drawn yarns
[0191] with the mechanical performance indices of monofilament
fineness 2.5 dtex, breaking strength 3.5 cN/dtex, elongation at
break 33.0%, interlacing degree 11/m, linear density deviation rate
1.0%, breaking strength CV value 5.0%, breaking elongation CV value
8.2%, and boiling water shrinkage rate 6.5%;
[0192] with the dyeing performance indices of dye uptake 91.8% (at
120.degree. C.), K/S value 25.56, color fastness to soaping level
5, color fastness to dry crocking level 5, and color fastness to
wet crocking level 6;
[0193] and with an intrinsic viscosity drop by 22% when stored at
25.degree. C. and R.H. 65% for 60 months.
Example 7
[0194] A method for preparing the fully dull polyester drawn yarns,
comprising the steps:
[0195] (1) Preparation of modified polyester
[0196] (1.1) Doping modification of Bi.sub.2O.sub.3
[0197] (a) evenly mixing a 2.5 wt % of Ca(NO.sub.3).sub.2 aqueous
solution and a 25 wt % of Bi.sub.2O.sub.3 nitric acid solution,
maintaining a 8:100 of molar ratio of Ca.sup.2+ and Bi.sup.3+;
[0198] (b) depositing the mixed solution by adding 2 mol/L of
ammonia water until pH value reaches 10, then washing and drying
(110.degree. C., 3 hr) the precipitate;
[0199] (c) after the treatment composed of a heating at 400.degree.
C. for 3 hr, a heating at 700.degree. C. for 2 hr and a cooling in
air, crushing the precipitate to doped Bi.sub.2O.sub.3 powder with
an average size of 0.45 .mu.m;
[0200] (1.2) Esterification
[0201] concocting terephthalic acid, ethylene glycol,
tetramethyldisiloxane diol and 2,2-difluoro-1,5-glutaric acid into
a slurry (in which the molar ration of terephthalic acid and
ethylene glycol is 1:1.3, the total addition of
tetramethyldisiloxane diol and 2,2-difluoro-1,5-glutaric acid with
a molar ratio of 2.5:3 is 5 mol % relative to the amount of
terephthalic acid), and adding in 0.06 wt % of the doped
Bi.sub.2O.sub.3, 0.04 wt % of antimony trioxide, 0.21 wt % of
titanium dioxide and 0.01 wt % of trimethyl phosphate (all are
relative to the amount of terephthalic acid), then carrying out the
esterification under a 0.3 MPa of nitrogen pressure at 260.degree.
C., finally ending the reaction when the water distillation rate
reaches 99% of the theoretical value;
[0202] (1.3) Polycondensation
[0203] after smoothly reducing the pressure from normal value to
500 Pa within 45 min, conducting the low vacuum polycondensation
for the esterification products at 280.degree. C. for 50 min, then
further reducing the pressure to 90 Pa and continuing the high
vacuum polycondensation at 277.degree. C. for 90 min, finally
obtaining the modified polyester with a molecular weight of 30000
and a molecular weight distribution index of 2.2;
[0204] (2) Spinning of fully dull polyester drawn yarn
[0205] through a FDY technological way including stages of
metering, spinneret extruding (at 295.degree. C.), cooling (at
22.degree. C.), oiling, stretching as well as heat setting (carried
on with the parameters of interlacing pressure 0.30 MPa, godet
roller 1 speed 2700 m/min, godet roller 1 temperature 86.degree.
C., godet roller 2 speed 4500 m/min, godet roller 2 temperature
135.degree. C.), and winding (4130 m/min), converting the modified
polyester into fully dull polyester drawn yarns
[0206] with the mechanical performance indices of monofilament
fineness 1.2 dtex, breaking strength 3.5 cN/dtex, elongation at
break 32.0%, interlacing degree 13/m, linear density deviation rate
0.88%, breaking strength CV value 4.5%, breaking elongation CV
value 9.0%, and boiling water shrinkage rate 7.0%;
[0207] with the dyeing performance indices of dye uptake 87.5% (at
120.degree. C.), K/S value 23.55, color fastness to soaping level
5, color fastness to dry crocking level 5, and color fastness to
wet crocking level 6;
[0208] and with an intrinsic viscosity drop by 26% when stored at
25.degree. C. and R.H. 65% for 60 months.
* * * * *