U.S. patent application number 15/803014 was filed with the patent office on 2018-05-03 for naphthoic acid ester plasticizers and method of making.
The applicant listed for this patent is ExxonMobil Research and Engineering Company. Invention is credited to Stephen T. COHN, Christine A. COSTELLO, Christopher M. EVANS, James R. LATTNER, Bernard F. LEROY, Didier A. NAERT.
Application Number | 20180118917 15/803014 |
Document ID | / |
Family ID | 62020250 |
Filed Date | 2018-05-03 |
United States Patent
Application |
20180118917 |
Kind Code |
A1 |
COHN; Stephen T. ; et
al. |
May 3, 2018 |
NAPHTHOIC ACID ESTER PLASTICIZERS AND METHOD OF MAKING
Abstract
Provided are compounds and processes of making and using such
compounds of the formula: ##STR00001## Wherein R=C4 to C15 linear
or branched alkyls ##STR00002## wherein R is a linear or branched
alkyl residue of a C4 to C15 alcohol. Such compounds provide
advantageous properties when used as plasticizers in polymer
compositions.
Inventors: |
COHN; Stephen T.; (Spring,
TX) ; EVANS; Christopher M.; (Kenmore, NY) ;
LATTNER; James R.; (LaPorte, TX) ; COSTELLO;
Christine A.; (Easton, PA) ; NAERT; Didier A.;
(Brussels, BE) ; LEROY; Bernard F.;
(C'eroux-Mousty, BE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
ExxonMobil Research and Engineering Company |
Annandale |
NJ |
US |
|
|
Family ID: |
62020250 |
Appl. No.: |
15/803014 |
Filed: |
November 3, 2017 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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62438495 |
Dec 23, 2016 |
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|
62416944 |
Nov 3, 2016 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C07C 2602/10 20170501;
C07C 67/303 20130101; C07D 307/92 20130101; C08L 27/06 20130101;
C07C 69/753 20130101; C07C 69/76 20130101; C07C 69/76 20130101;
C07C 69/76 20130101; C07C 67/303 20130101; G01R 33/46 20130101;
C07C 67/08 20130101; C07C 67/12 20130101; C08L 27/06 20130101; C07C
67/12 20130101; C08K 5/12 20130101; C08K 5/09 20130101; C08L
23/0853 20130101; C07C 69/616 20130101; C07C 69/753 20130101; C08F
14/06 20130101; C07C 67/303 20130101; C07C 2602/28 20170501; C08K
5/0016 20130101; C07C 67/08 20130101; C08K 5/12 20130101; C07C
69/76 20130101; C08L 75/04 20130101; C08L 33/10 20130101 |
International
Class: |
C08K 5/09 20060101
C08K005/09; C07C 69/616 20060101 C07C069/616; C08K 5/00 20060101
C08K005/00; C08F 14/06 20060101 C08F014/06 |
Claims
1. A plasticizer comprising a compound selected from the group
consisting of ##STR00041## Wherein R.dbd.C4 to C15 linear or
branched alkyls ##STR00042## wherein R is a linear or branched
alkyl residue of a C4 to C15 alcohol, and combinations thereof.
2. The plasticizer of claim 1, wherein R is a linear C9-C15
alkyl.
3. The plasticizer of claim 1, wherein R is a C7 to C15 branched
alkyl.
4. The plasticizer of claim 1, wherein R is the hydrocarbon residue
of a C7 to C15 OXO-alcohol averaging from 0.2 to 4.0 branches per
residue.
5. The plasticizer of claim 4, wherein the hydrocarbon residue
averages from 1.8 to 3.8 branches per residue.
6. The plasticizer of claim 5, wherein the hydrocarbon residue
averages at least 1.3 to 3.0 methyl branches per residue.
7. The plasticizer of claim 6, wherein the hydrocarbon residue
averages from 1 to 2.5 pendant methyl branches per residue.
8. The plasticizer of claim 1, wherein the viscosity at a shear
rate of 334 sec..sup.-1 ranges from 20 to 80 centipoise.
9. The plasticizer of claim 1, further comprising a second
plasticizer comprising one or more of di-n-butyl terephthalate,
diisobutyl terephthalate, di-n-octyl terephthalate, diisooctyl
terephthalate, di-2-ethylhexyl terephthalate, di-n-nonyl
terephthalate, diisononyl terephthalate, di-n-decyl terephthalate,
di-2-propyl heptyl terephthalate, diisodecyl terephthalate,
di-n-nonyl phthalate, diisononyl phthalate, di-n-decyl phthalate,
diisodecyl phthalate, di-2-propyl heptyl phthalate, di-n-undecyl
phthalate, ditridecyl phthalate, diisotridecyl phthalate,
di-n-propyl isophthalate, di-n-nonyl isophthalate, diisononyl
isophthalate, di-n-decyl isophthalate, diisodecyl isophthalate,
di-2-propyl heptyl isophthalate, di-n-undecyl isophthalate,
diisotridecyl isophthalate, isononyl benzoate, nonyl benzoate,
isodecyl benzoate, decyl benzoate, 2-propylheptyl benzoate,
isoundecyl benzoate, isotridecyl benzoate, di-heptyl cylohexanoate,
di-2-ethylhexyl cylochexanoate, di-n-nonyl cylochexanoate,
diisononyl cylochexanoate, di-n-decyl cylochexanoate, diisodecyl
cylochexanoate, di-2-propyl heptyl cylochexanoate, diheptyl
adipate, dioctyl adipate, diisononyl adipate, diisodecyl adipate,
di 2-propylheptyl adipate, dipropylene glycol dibenzoate,
diethylene glycol dibenzoate, triethylene glycol dibenzoate, or
mixtures thereof.
10. A polymer composition comprising a thermoplastic polymer and at
least one plasticizer comprising a compound selected from the group
consisting of ##STR00043## Wherein R.dbd.C4 to C15 linear or
branched alkyls ##STR00044## wherein R is a linear or branched
alkyl residue of a C4 to C15 alcohol, and combinations thereof.
11. The polymer composition of claim 10, wherein the thermoplastic
polymer is selected from the group consisting of vinyl chloride
resins, polyesters, polyurethanes, ethylene-vinyl acetate
copolymer, rubbers, poly(meth)acrylics and combinations
thereof.
12. The polymer composition of claim 11, wherein the thermoplastic
polymer is polyvinyl chloride.
13. The polymer composition of claim 12, wherein the thermoplastic
polymer is a PVC suspension, a PVC microsuspension, a PVC emulsion,
or a combination thereof.
14. The polymer composition of claim 10, wherein R is a linear
C9-15 alkyl.
15. The polymer composition of claim 10, further comprising a
second plasticizer comprising one or more of alkyl terephthalate,
alkyl phthalate, a C7 to C13 alkyl benzoate ester, dibenzoate
ester, an ester of cyclohexane polycarboxylic acid, and dialkyl
adipate.
16. The polymer composition of claim 10, wherein thermoplastic
polymer is present at 99 to 40 wt % and plasticizer is present at 1
to 60 wt %, based on the total weight of the composition.
17. The polymer composition of claim 10, wherein the composition
comprises plasticizer in an amount of from 5 to 90 phr.
18. The polymer composition of claim 10, further comprising at
least one additive selected from the group consisting of trialkyl
trimellite, alkylsulphonic ester, glycerol ester, isosorbide ester,
citric ester, alkylpyrrolidone, and epoxidized oil.
19. The polymer composition of claim 10, further comprising at
least one additive selected from the group consisting of a filler,
a pigment, a matting agent, a heat stabilizer, an antioxidant, a UV
stabilizer, a flame retardant, a viscosity regulator, a solvent, a
deaerating agent, an adhesion promoter, a process aid, and a
lubricant.
20. A process for making a naphthoic acid ester plasticizer
selected from the group consisting of ##STR00045## Wherein R.dbd.C4
to C15 linear or branched alkyls ##STR00046## wherein R is a linear
or branched alkyl residue of a C4 to C15 alcohol, and combinations
thereof, comprising the steps of: reacting naphthalene with carbon
dioxide under conditions appropriate to form naphthoic acid; and
reacting said acid group with a C4 to C15 linear or branched
alcohol under esterification conditions to form a naphthoic acid
ester plasticizer.
21. The process of claim 20, wherein the C4 to C15 linear or
branched alcohol is an OXO-alcohol.
22. A process for making a naphthoic acid ester plasticizer
selected from the group consisting of ##STR00047## Wherein R.dbd.C4
to C15 linear or branched alkyls ##STR00048## wherein R is a linear
or branched alkyl residue of a C4 to C15 alcohol, and combinations
thereof, comprising the steps of: methylating naphthalene under
conditions appropriate to form methylnaphthalene; oxidizing
methylnaphthalene under conditions appropriate to form naphthoic
acid; and reacting said acid group with a C4 to C15 linear or
branched alcohol under esterification conditions to form a
naphthoic acid ester plasticizer.
23. The process of claim 22, wherein the C4 to C15 linear or
branched alcohol is an OXO-alcohol.
24. A process for making a naphthoic acid ester plasticizer
selected from the group consisting of ##STR00049## Wherein R.dbd.C4
to C15 linear or branched alkyls ##STR00050## wherein R is a linear
or branched alkyl residue of a C4 to C15 alcohol, and combinations
thereof, comprising the steps of: alkylating benzene or toluene
with pentene or butene under conditions appropriate to form alkyl
benzene or alkyl toluene; dehydrocyclizating alkyl benzene or alkyl
toluene under conditions appropriate to form methylnaphthalene;
oxidizing methylnaphthalene under conditions appropriate to form
naphthoic acid; and reacting said acid group with a C4 to C15
linear or branched alcohol under esterification conditions to form
a naphthoic acid ester plasticizer.
25. The process of claim 24, wherein the C4 to C15 linear or
branched alcohol is an OXO-alcohol.
26. The plasticizer of claim 1, wherein the plasticizer is used in
a wire and cable coating formulation, cable filling compound, floor
covering, wall covering, tarpaulin, coated textile, film, roofing
sheet, banner, synthetic leather, packaging material, medical
article, toy, seal, or automobile interior article.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Application No. 62/438,495, filed on Dec. 23, 2016, the entire
contents of which are incorporated herein by reference.
[0002] This application also claims the benefit of U.S. Provisional
Application No. 62/416,944, filed on Nov. 3, 2016, the entire
contents of which are incorporated herein by reference.
FIELD
[0003] This disclosure is related to a potential route to aromatic
OXO-ester plasticizers. More particularly it relates to naphthoic
acid ester plasticizers, their use in polymer compositions and
methods of making therein.
BACKGROUND
[0004] Plasticizers are incorporated into a resin (usually a
plastic or elastomer) to increase the flexibility, workability, or
dispensability of the resin. The largest use of plasticizers is in
the production of "plasticized" or flexible polyvinyl chloride
(PVC) products. Typical uses of plasticized PVC include films,
sheets, tubing, coated fabrics, wire and cable insulation and
jacketing, toys, flooring materials such as vinyl sheet flooring or
vinyl floor tiles, adhesives, sealants, inks, and medical products
such as blood bags and tubing, and the like.
[0005] Other polymer systems that use small amounts of plasticizers
include polyvinyl butyral, acrylic polymers, nylon, polyolefins,
polyurethanes, and certain fluoroplastics. Plasticizers can also be
used with rubber (although often these materials fall under the
definition of extenders for rubber rather than plasticizers). A
listing of the major plasticizers and their compatibilities with
different polymer systems is provided in "Plasticizers," A. D.
Godwin, in Applied Polymer Science 21st Century, edited by C. D.
Craver and C. E. Carraher, Elsevier (2000); pp. 157-175.
[0006] Plasticizers can be characterized on the basis of their
chemical structure. The most important chemical class of
plasticizers is phthalic acid esters, which accounted for 85%
worldwide of PVC plasticizer usage in 2002. However, in the recent
past there has been an effort to decrease the use of low molecular
weight phthalate esters as plasticizers in PVC, particularly in end
uses where the product contacts food, such as bottle cap liners and
sealants, medical and food films, or for medical examination
gloves, blood bags, and IV delivery systems, flexible tubing, or
for toys, and the like. For these and most other uses of
plasticized polymer systems, however, a successful substitute for
phthalate esters has heretofore not materialized.
[0007] One such suggested alternative to phthalates are esters
based on cyclohexanoic acid. In the late 1990's and early 2000's,
various compositions based on cyclohexanoate, cyclohexanedioates,
and cyclohexanepolyoate esters were said to be useful for a range
of goods from semi-rigid to highly flexible materials. See, for
instance, WO 99/32427, WO 2004/046078, WO 2003/029339, WO
2004/046078, U.S. Application No. 2006-0247461, and U.S. Pat. No.
7,297,738.
[0008] Other suggested alternatives include esters based on benzoic
acid (see, for instance, U.S. Pat. No. 6,740,254 and U.S.
Provisional Patent Application No. 61/040,480, filed Mar. 28, 2008
and polyketones, such as described in U.S. Pat. No. 6,777,514 and
U.S. Pat. No. 8,115,034. Epoxidized soybean oil, which has much
longer alkyl groups (C.sub.16 to C.sub.18) has been tried as a
plasticizer, but is generally used as a PVC stabilizer. Stabilizers
are used in much lower concentrations than plasticizers. U.S.
Provisional Patent Application No. 61/203,626, filed Dec. 24, 2008,
discloses triglycerides with a total carbon number of the triester
groups between 20 and 25, produced by esterification of glycerol
with a combination of acids derived from the hydroformylation and
subsequent oxidation of C.sub.3 to C.sub.9 olefins, having
excellent compatibility with a wide variety of resins and that can
be made with a high throughput.
[0009] U.S. Pat. No. 3,284,220 to Anagnostopoulos et al. discloses
substituted phenyl ethers of certain mono- and polycarboxylic
naphthoic acids and their use as stabilizers for polymeric
substances.
[0010] U.S. Pat. No. 5,095,135 to Yamada et al. discloses a process
for the preparation of naphthalene carboxylic acid esters in which
a substituted naphthalene is oxidized with molecular oxygen in the
presence of a heavy metal-based catalyst in a solvent comprising a
lower aliphatic monocarboxylic acid to form a naphthalene
carboxylic acid and the resulting acid is then esterified. The
esterified product is purified by washing, recrystallization, and
distillation in that order. Heavy metals are recovered as
carbonates from filtrates and washings obtained by separation of
crude acid and ester products and by washing thereof.
[0011] U.S. Patent Publication No. 2014/0179845, herein
incorporated by reference in its entirely, discloses compounds and
processes of making compounds of the formula:
##STR00003##
[0012] wherein x=4 to 8, R is H, C.sub.1 to C.sub.4 alkyl,
--C(O)OR.sub.1 or --OC(O)R.sub.1, y=4 to 8, R' is H, C.sub.1 to
C.sub.4 alkyl, and at least one R' is --C(O)OR.sub.1 or
--OC(O)R.sub.1, wherein R.sub.1 is a branched C.sub.4 to C.sub.14
alkyl, and their use in polymer compositions. U.S. Patent
Publication No. 2014/0179845 does not disclose or suggest the
potential of manipulating plasticizer properties by changing the
position of the ester group on the naphthalene ring or by varying
the branching and length of the alcohol used to make the ester.
[0013] There is an increased interest in developing new
plasticizers that offer alternatives to low molecular weight
phthalates and which possess good plasticizer performance
characteristics while remaining competitive economically. What is
needed is a plasticizer with the correct balance of polarity or
solubility and volatility and viscosity to have acceptable
plasticizer compatibility with the resin. Plasticizers need also to
exhibit good hydrolytic and thermal stability, low pour point, good
aging performance and low temperature properties.
SUMMARY
[0014] In one aspect, the present application is directed to
plasticizers comprising a compound selected from the group
consisting of
##STR00004## [0015] Wherein R.dbd.C4 to C15 linear or branched
alkyls
##STR00005##
[0015] wherein R is a linear or branched alkyl residue of a C4 to
C15 alcohol, and combinations thereof.
[0016] In another aspect, the present application is directed to
polymer compositions comprising a thermoplastic polymer and at
least one plasticizer comprising a compound selected from the group
consisting of
##STR00006## [0017] Wherein R.dbd.C4 to C15 linear or branched
alkyls
##STR00007##
[0017] wherein R is a linear or branched alkyl residue of a C4 to
C15 alcohol, and combinations thereof, in which the thermoplastic
polymer can be selected from the group consisting of vinyl chloride
resins, polyesters, polyurethanes, ethylene-vinyl acetate
copolymer, rubbers, poly(meth)acrylics and combinations
thereof.
[0018] In yet another aspect, the present application is directed
to a process for making a naphthoic acid ester plasticizer selected
from the group consisting of
##STR00008## [0019] Wherein R.dbd.C4 to C15 linear or branched
alkyls
##STR00009##
[0019] wherein R is a linear or branched alkyl residue of a C4 to
C15 alcohol, and combinations thereof, comprising the steps of:
reacting naphthalene with carbon dioxide under conditions
appropriate to form naphthoic acid; and reacting said acid group
with a C4 to C15 linear or branched alcohol under esterification
conditions to form naphthoic acid ester plasticizer. The
plasticizer can subsequently be hydrogenated with hydrogen over a
hydrogenation catalyst to form one or more saturated rings.
[0020] In still yet another aspect, the present application is
directed to a process for making a naphthoic acid ester plasticizer
selected from the group consisting of
##STR00010## [0021] Wherein R.dbd.C4 to C15 linear or branched
alkyls
##STR00011##
[0021] wherein R is a linear or branched alkyl residue of a C4 to
C15 alcohol, and combinations thereof, comprising the steps of:
methylating naphthalene under conditions appropriate to form
methylnaphthalene; oxidizing methylnaphthalene under conditions
appropriate to form naphthoic acid; and reacting said acid group
with a C4 to C15 linear or branched alcohol under esterification
conditions to form a naphthoic acid ester plasticizer. The
plasticizer can subsequently be hydrogenated with hydrogen over a
hydrogenation catalyst to form one or more saturated rings.
[0022] In still yet another further aspect, the present application
is directed to a process for making a naphthoic acid ester
plasticizer selected from the group consisting of
##STR00012## [0023] Wherein R.dbd.C4 to C15 linear or branched
alkyls
##STR00013##
[0023] wherein R is a linear or branched alkyl residue of a C4 to
C15 alcohol, and combinations thereof, comprising the steps of:
alkylating benzene or toluene with pentene or butene under
conditions appropriate to form alkyl benzene or alkyl toluene;
dehydrocyclizating alkyl benzene or alkyl toluene under conditions
appropriate to form methylnaphthalene; oxidizing methylnaphthalene
under conditions appropriate to form naphthoic acid; and reacting
said acid group with a C4 to C15 linear or branched alcohol under
esterification conditions to form a naphthoic acid ester
plasticizer. The plasticizer can subsequently be hydrogenated with
hydrogen over a hydrogenation catalyst to form one or more
saturated rings.
[0024] In particularly preferred embodiments, the naphthoic acid
ester plasticizers can be those wherein R is a hydrocarbon residue
having an average carbon number ("ACN") of C4 to C15 or an
OXO-alcohol having a C4 to C15 alkyl chain, preferably a C7 to C15,
C7 to C14, C9 to C14, C10 to C15, or C10 to C14 alkyl chain, such
as nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, and
isomers thereof. The OXO-alcohol may have a degree of branching
averaging from 0.2 to 4.0 branches per residue or from 0.2 to 1.7,
1.8 to 3.8, 2.0 to 3.6, or 2.1 to 3.5 branches per residue. For
purposes of this specification, the term "average carbon number" or
ACN means the carbon number of a single molecule or the average of
individual molecule carbon numbers in a group of molecules. The
average carbon number (ACN) of the alcohols can be determined by
.sup.1H NMR. .sup.1H NMR methods or .sup.13C NMR methods can also
be used to determine the degree of branching of the alcohol.
According to the present invention, it is preferable to determine
the degree of branching with the aid of .sup.1H NMR spectroscopy on
a solution of esters in deuterochloroform (CDCl.sub.3). The spectra
are recorded, by way of example, by dissolving 20 mg of substance
in 0.6 ml of CDCl.sub.3, comprising 1% by weight of
tetramethylsilane (TMS), and charging the solution to an NMR tube
whose diameter is 5 mm. Both the substance to be studied and the
CDCl.sub.3 used can first be dried over a molecular sieve in order
to exclude any errors in the values measured due to possible
presence of water. The method of determination of the degree of
branching is advantageous in comparison with other methods for the
characterization of alcohol moieties, described by way of example
in WO 03/029339, since water contamination in essence has no effect
on the results measured and their evaluation. In principle, any
commercially available NMR equipment can be used for the
NMR-spectroscopic studies. The present NMR-spectroscopic studies
used a Varian INOVA-500 spectrometer. The spectra were recorded at
a temperature of 300 K using a delay of d1=10 seconds, 64 scans, a
pulse length of 9.7 .mu.s and a sweep width of 13 000 Hz, using a 5
mm BBO (broad band observer) probe head. The resonance signals are
recorded in comparison with the chemical shifts of
tetramethylsilane (TMS=0 ppm) as the internal standard. Comparable
results may be obtained with other commercially available NMR
equipment using the same operating parameters.
[0025] The degree of branching B can therefore be calculated from
the measured intensity ratio in accordance with the following
formula:
B=(2/3*I(CH.sub.3)/I(OCH.sub.2))-1
B is degree of branching, I(CH.sub.3) is the area integral
essentially attributed to the methyl hydrogen atoms, and
I(OCH.sub.2) is the area integral for the methylene hydrogen atoms
adjacent to the oxygen atom.
[0026] The average carbon number (ACN) can therefore be calculated
from the measured intensity ratio in accordance with the following
formula:
ACN=I(CH.sub.2,CH(OH)+I(CH.sub.3)/I(OCH.sub.2)
where ACN is the average carbon number, I(CH.sub.3) is the area
integral essentially attributed to the methyl hydrogen atoms, and
I(OCH.sub.2) is the area integral for the methylene hydrogen atoms
adjacent to the oxygen atom.
[0027] Advantageously, in order to obtain optimum aging performance
(e.g., sufficiently low plasticizer volatility), the average number
of carbons in all hydrocarbon residues should be more than 9
carbons, such as for example 10, 11, 12, 13, 14 or 15 carbons.
[0028] The naphthoic acid ester plasticizer of the present
disclosure when mixed and processed with PVC has been found to
provide good plastisol rheology, good gelation and plasticizing
efficiency.
[0029] In particularly preferred embodiments, the naphthoic acid
ester plasticizer of the present disclosure can be represented by,
but is not limited to, any of the following chemical
structures:
##STR00014##
wherein R is a linear or branched alkyl residue of a C4 to C15
alcohol, such as linear or branched tridecyl-1-naphthoate or linear
or branched tridecyl-2-naphthoate.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] FIG. 1 is an .sup.1H NMR spectrum of an inventive sample of
dodecyl-2-napththoate.
[0031] FIG. 2 is a .sup.13C NMR spectrum of an inventive sample of
dodecyl-2-napththoate.
[0032] FIG. 3 is a graph of plastisol viscosity versus shear rate
after one day for an inventive sample of dodecyl-2-napththoate.
[0033] FIG. 4 is a graph of elastic modulus (storage modulus)
versus temperature (gelation curve) for an inventive sample of
dodecyl-2-napththoate.
[0034] FIG. 5 is a graph of dry blending properties of certain
inventive samples versus a DINP standard.
DETAILED DESCRIPTION
[0035] All numerical values within the detailed description and the
claims herein are modified by "about" or "approximately" the
indicated value, and take into account experimental error and
variations that would be expected by a person having ordinary skill
in the art.
[0036] There is an increased interest in developing new general
purpose plasticizers that possess good compatibility with PVC while
being cost competitive. The present disclosure is directed toward
OXO-based ester plasticizers that can be made from low cost feeds
and employ fewer manufacturing steps in order to meet economic
targets.
Plasticizer and Polymer Compositions
[0037] It has been determined that plasticizers comprising one or
more compounds selected from the group consisting of:
##STR00015## [0038] Wherein R.dbd.C4 to C15 linear or branched
alkyls
##STR00016##
[0038] wherein R is a linear or branched alkyl residue of a C4 to
C15 alcohol, and combinations thereof exhibit comparable
performance to general purpose plasticizers for thermoplastic
polymers, such as di-2-ethyl hexyl phthalate (DEHP), or di-isononyl
phthalate (DINP) in flexible PVC. R may be a linear or branched
alkyl group, including a C4, C5, C6, C7, C8, C9, C10, C11, C12,
C13, C14, or C15 linear or branched alkyl group or combinations
thereof. Particularly preferred linear alkyl groups are C7-C15,
C9-C15, C7-C14, C9-C14, and C11-C15 linear alkyl groups, such as
C11, C13, and/or C15 linear alkyl groups. Particularly preferred
branched alkyl groups are C7-C15, C9-C15, C7-C14, C9-C14, and
C11-C15 branched alkyl groups, such as C11, C13, and/or C15
branched alkyl groups.
[0039] The plasticizers of the present invention may have a dynamic
viscosity measured according to ASTM D7042 of from 10 to 200 mPas,
such as from 30 to 90 or 40 to 90 mPas. One can modify plasticizer
neat properties and performance attributes in polymer compositions,
such as gelation and fusion, volatility and aging performance,
migration and extraction resistance, compatibility with PVC, low
pour point and low temperature properties, and hydrolytic, chemical
and thermal stability by varying the number of carbons in the alkyl
chains R, the degree of branching of the alkyl chains R, and also
the position of the ester functional group. It has been found that
if the 20.degree. C. kinematic viscosity or 20.degree. C.
cone-and-plate viscosity is higher than 250 mm.sup.2/sec, as
measured by an appropriate ASTM test, it may affect the plasticizer
process ability during formulation and require heating the
plasticizer to ensure good transfer during storage and mixing of
the polymer and the plasticizer.
[0040] The inventive plasticizers possess good performance
characteristics and can be produced economically. They have a good
balance of polarity/solubility and volatility/viscosity to have
compatibility with various resins. They also exhibit hydrolytic and
thermal stability, low pour point, good aging performance and low
temperature properties.
[0041] In another embodiment of the invention, a polymer
composition comprising a thermoplastic polymer and at least one
plasticizer comprising at least one compound selected from the
group consisting of
##STR00017## [0042] Wherein R.dbd.C4 to C15 linear or branched
alkyls
##STR00018##
[0042] wherein R is a linear or branched alkyl residue of a C4 to
C15 alcohol, and combinations thereof provides particularly
advantageous plasticizer performance properties. Non-limiting
exemplary thermoplastic polymers include vinyl chloride resins,
polyesters, polyurethanes, silylated polymers, polysulfides,
acrylics, ethylene-vinyl acetate copolymer, rubbers,
poly(meth)acrylics, and combinations thereof. Polyvinyl chloride
(PVC) is a particularly preferred thermoplastic with the
plasticizers of the present disclosure.
[0043] In certain embodiments of the invention, particularly
preferred plasticizer compounds of the present disclosure include
the following structures:
##STR00019## ##STR00020##
wherein R is a linear or branched alkyl residue of a C4 to C15
alcohol. Examples of commercially available alcohols that may be
useful in making the inventive plasticizers include but are not
limited to NEODOL 1, 91, 23, 25, and 135 available from Shell;
isodecyl alcohol (EXXAL 10, available from ExxonMobil Chemical
Company); and 2-propyl heptanol (available from BASF, Evonik and
Perstorp).
Methods of Making Such Plasticizers
[0044] The naphthoic acid mono-ester plasticizers of the instant
disclosure are formed by first forming naphthoic acid. The
naphthoic acid is then esterified by reaction with a linear alcohol
or a branched alcohol to form the naphthoic acid mono-ester
plasticizers of the instant disclosure. The alcohol used is
preferably an OXO-alcohol
[0045] One route to naphthoic acid mono-ester plasticizers of the
present disclosure is by catalyzed oxidation of methyl naphthalene
to form a naphthoic acid, as follows:
##STR00021##
Subsequently, the naphthoic acid can be esterified by reaction with
a linear or branched alcohol to form the naphthoic acid mono-esters
of the present disclosure as shown below.
##STR00022##
[0046] Another route to forming the naphthoic acid of the present
disclosure is by direct carboxylation of naphthalene via carbon
dioxide as shown below. Another route to naphthoic acid of the
present disclosure is by direct methylation of naphthalene followed
by oxidation as shown below and as also described above.
##STR00023##
[0047] Subsequently, the naphthoic acid can be esterified by
reaction with a linear or branched alcohol to form the naphthoic
acid mono-esters of the present disclosure. The alcohol used is
preferably an OXO-alcohol.
[0048] Yet another possible route for forming the naphthoic acid of
the present disclosure is by using benzene or toluene as the
starting material. The benzene or toluene is alkylated with pentene
and/or butene followed by dehydrocyclization as shown below to form
methylnaphthalene.
##STR00024##
Subsequently, methylnaphthalene is oxidized under conditions
appropriate to form naphthoic acid. The naphthoic acid is then
esterified with a C4 to C15, preferably a C9 to C15, linear or
branched alcohol under esterification conditions to form a
naphthoic acid mono-ester. The mono-ester can subsequently be
hydrogenated with hydrogen over a hydrogenation catalyst to form
one or more saturated rings.
[0049] In more preferred embodiments, the naphthoic acids are
esterified with OXO-alcohols, which are mixed linear and branched
alcohol isomers, the formation of which is described in more detail
below.
[0050] An "OXO-alcohol" is an organic alcohol, or mixtures of
organic alcohols, which is prepared by hydroformylating an olefin,
followed by hydrogenation to form the alcohols. Typically, the
olefin is formed by light olefin oligomerization over heterogenous
acid catalysts, which olefins are readily available from refinery
processing operations. The reaction results in mixtures of
longer-chain, branched olefins, which subsequently form longer
chain, branched alcohols or acids, as described in U.S. Pat. No.
6,274,756, incorporated herein by reference in its entirety. The
OXO-alcohols consist of multiple isomers of a given chain length
due to the various isomeric olefins obtained in the oligomerization
process, in tandem with the multiple isomeric possibilities of the
hydroformylation step.
[0051] An "OXO-ester" is a compound having at least one functional
ester moiety within its structure derived from esterification of
either an acid or alcohol compound with an OXO-alcohol or OXO-acid,
respectively.
[0052] "Hydroformylating" or "hydroformylation" is the process of
reacting a compound having at least one carbon-carbon double bond
(an olefin) in an atmosphere of carbon monoxide and hydrogen over a
cobalt or rhodium catalyst, which results in addition of at least
one aldehyde moiety to the underlying compound. U.S. Pat. No.
6,482,972, which is incorporated herein by reference in its
entirety, describes the hydroformylation (OXO) process.
[0053] Branched aldehydes can be produced by hydroformylation of C3
to C15 olefins; in turn, some of these olefins have been produced
by propylene and/or butene oligomerization over solid phosphoric
acid or zeolite catalysts. The resulting C4 to C15 aldehydes can
then be recovered from the crude hydroformylation product stream by
fractionation to remove unreacted olefins. These C4 to C15
aldehydes can then hydrogenated to alcohols (OXO-alcohols). Single
carbon number alcohols can be used in the esterification of the
aromatic acids described above, or differing carbon numbers can be
used to optimize product cost and performance requirements. The
"OXO" technology provides cost advantaged alcohols and acids. Other
options are considered, such as hydroformylation of C4-olefins to
C5-aldehydes, followed by hydrogenation to C5-alcohols, or aldehyde
dimerization followed by hydrogenation or oxidation to C10
alcohols. It is understood that the term "branched" describes the
overall isomeric mixture of the aldehydes (and subsequent acids,
alcohols, and R1 residues). Thus, a "branched" OXO-aldehyde,
alcohol, or residue contains some portion of linear isomers mixed
in with the individual branched isomers.
[0054] "Hydrogenating" or "hydrogenation" is addition of hydrogen
(H2) to a double-bonded functional site of a molecule, such as in
the present case the addition of hydrogen to the aldehyde to form
the corresponding alcohol, and saturation of the double bonds in an
aromatic ring. Conditions for hydrogenation of an aldehyde are
well-known in the art and include, but are not limited to
temperatures of 0-300.degree. C., pressures of 1-500 atmospheres,
and the presence of homogeneous or heterogeneous hydrogenation
catalysts such as Pt/C, Pt/Al.sub.2O.sub.3 or
Pd/Al.sub.2O.sub.3.
[0055] Alternatively, OXO-alcohols can be prepared by aldol
condensation of shorter-chain aldehydes to form longer chain
aldehydes, as described in U.S. Pat. No. 6,274,756, followed by
oxidation or hydrogenation to form the OXO-acids or OXO-alcohols,
respectively.
[0056] "Esterifying" or "esterification" is reaction of a
carboxylic acid moiety, such as an anhydride, with an organic
alcohol moiety to form an ester linkage. Esterification conditions
are well-known in the art and include, but are not limited to,
temperatures of 0-300.degree. C., and the presence or absence of
homogeneous or heterogeneous esterification catalysts such as Lewis
or Bronsted acid catalysts.
[0057] As discussed above, the resulting OXO-alcohols can be used
individually or together in mixtures having different chain
lengths, or in isomeric mixtures of the same carbon chain length to
make mixed esters for use as plasticizers. This mixing of carbon
numbers and/or levels of branching can be advantageous to achieve
the desired compatibility with PVC for the respective core alcohol
used for the polar moiety end of the plasticizer, and to meet other
plasticizer performance properties. The preferred OXO-alcohols are
those having from 4 to 15 carbons, more preferably C11 to C15
alcohols, and even more preferably C11, C13, C15 alcohols,
depending on the number of ester moieties and the desired
volatility of the compound.
[0058] The overall isomeric distribution of OXO-alcohols may be
described quantitatively by parameters such as average branch
content per molecule or per chain position. Branching may be
determined by Nuclear Magnetic Resonance (NMR) spectroscopy.
[0059] In one embodiment, preferred OXO-alcohols are those which
result in R being a hydrocarbon residue of a C4 to C15, C7 to C15,
or C11 to C15 OXO-alcohol averaging from 0.2 to 4.0, 0.2 to 1.7,
1.8 to 3.8, 2.0 to 3.6, or 2.1 to 3.5 branches per residue.
[0060] Typical branching characteristics of OXO-alcohols are
provided in Table 1 below.
TABLE-US-00001 TABLE 1 .sup.13C NMR Branching Characteristics of
Typical OXO-Alcohols. Total Pendant Pendant OXO- Avg. % of
.alpha.-Carbons .beta.-Branches per Methyls per Methyls per Ethyls
per Alcohol Carbon No. w/Branches.sup.a Molecule.sup.b
Molecule.sup.c Molecule.sup.d Molecule C.sub.4.sup.e 4.0 0 0.35
1.35 0.35 0 C.sub.5.sup.f 5.0 0 0.30 1.35 0.35 0 C.sub.6 -- -- --
-- -- -- C.sub.7 7.3 0 0.15 1.96 0.99 0.04 C.sub.8 8.6 0 0.09 3.0
1.5 -- C.sub.9 9.66 0 0.09 3.4 -- -- C.sub.10 10.2 0 0.16 3.2 -- --
C.sub.12 12.2 0 -- 4.8 -- -- C.sub.13 13.1 0 -- 4.4 -- -- -- Data
not available. .sup.aCOH carbon. .sup.bBranches at the-CCH.sub.2OH
carbon. .sup.cThis value counts all methyl groups, including
C.sub.1 branches, chain end methyls, and methyl endgroups on
C.sub.2+ branches. .sup.dC.sub.1 branches only. .sup.eCalculated
values based on an assumed molar isomeric distribution of 65%
n-butanol and 35% isobutanol (2-methylpentanol). .sup.fCalculated
values based on an assumed molar isomeric distribution of 65%
n-pentanol, 30% 2-ethylbutanol, and 5% 3-methylbutanol.
[0061] In general, for every polymer to be plasticized, a
plasticizer is required with the correct balance of solubility,
volatility, and viscosity to have acceptable compatibility with the
resin. Volatility affects the long-term aging performance of
flexible PVC. Higher volatility plasticizers can be lost by
evaporation or diffuse out of the plastic material causing
brittleness and article failure. The plasticizer neat volatility
can be roughly predicted by the neat plasticizer weight loss at
220.degree. C. using thermogravimetric analysis (see Tables 2 and
3). Neat plasticizer volatility can also be predicted by measuring
the plasticizer weight loss at 24 hours at 155.degree. C. according
to ASTM D1048.
[0062] When C11 to C15 OXO-alcohols are used as reactants for the
esterification reactions described above, the resulting OXO-esters
are relatively high-boiling liquids (having volatility comparable
to commercial plasticizers like DINP, DOTP, or Hexamol DINCH.RTM.),
which are readily incorporated into polymer formulations as
plasticizers (see Tables 2 and 3 below).
Polymer Compositions
[0063] The polymer composition comprising a thermoplastic polymer
and at least one plasticizer blend described herein may optionally
contain further additional plasticizers other than those produced
herein, such as: dialkyl (ortho)phthalate, preferably having 4 to
13 carbon atoms in the alkyl chain; trialkyl trimellitates,
preferably having 4 to 10 carbon atoms in the side chain; dialkyl
adipates, having 4 to 13 carbon atoms; dialkyl sebacates preferably
having 4 to 13 carbon atoms; dialkyl azelates preferably having 4
to 13 carbon atoms; preferably dialkyl terephthalates each
preferably having 4 to 8 carbon atoms and more particularly 4 to 7
carbon atoms in the side chain; alkyl
1,2-cyclohexanedicarboxylates, alkyl 1,3-cyclohexanedicarboxylates
and alkyl 1,4-cyclohexanedicarboxylates, and preferably here alkyl
1,2-cyclohexanedicarboxylates each preferably having 4 to 13 carbon
atoms in the side chain; dibenzoic esters of glycols; mono benzoate
esters with preferably an alkyl radical of 9 to 13 carbon atoms;
alkylsulfonic esters of phenol with preferably one alkyl radical
containing 8 to 22 carbon atoms; polymeric plasticizers (based on
polyester in particular), glyceryl esters, acetylated glycerol
esters, epoxy estolide fatty acid alkyl esters, citric triesters
having a free OH group or are acetylated with for example alkyl
radicals of 4 to 9 carbon atoms, alkylpyrrolidone derivatives
having alkyl radicals of 4 to 18 carbon atoms and also alkyl
benzoates, preferably having 7 to 13 carbon atoms in the alkyl
chain. In all instances, the alkyl radicals can be linear or
branched and the same or different.
[0064] Examples of commercially available benzenepolycarboxylic
acid esters potentially useful herein as additional plasticizers to
blend with the inventive plasticizers include phthalates such as
PALATINOL AH (di-(2-ethylhexyl) phthalate; PALATINOL N (diisononyl
phthalate); VESTINOL 9 (diisonyl phthalate); PALATINOL Z
(diisodecyl phthalate); PALATINOL 10-P (di-(2-propylheptyl)
phthalate); PALATINOL 711P (heptylundecyl phthalate); PALATINOL 911
(nonylundecyl phthalate); PALATINOL 11P-E (diundecyl phthalate);
PALATINOL 11P-E; JAYFLEX DINP; JAYFLEX DIDP; JAYFLEX DIUP; JAYFLEX
DTDP; and EMOLTENE 100. Examples of cyclohexane polycarboxylic acid
esters useful herein include Hexamoll DINCHM (diisonyl
cyclohexanoate); ELATUR CH (diisonyl cyclohexanoate); NanYa.TM.
DPEH (bis(2-ethyl hexyl)cyclohexanoate); and NanYa.TM. DPIN
(diisononyl cyclohexanoate). Examples of commercially available
adipates useful herein include PLASTOMOLL DOA (diisononyl adipate);
OXSOFT DOA; EASTMAN DOA (di-(2-ethylhexyl) adipates); and
PLASTOMOLL DNA (diisononyl adipate). Examples of commercially
available alkyl benzoates useful herein include: VESTINOL INB
(isononyl benzoate); JAYFLEX MB10 (isodecyl benzoate); BENZOFLEX
131 (isodecyl benzoate); and UNIPLEX 131 (isodecyl benzoate).
Particularly useful examples of plasticizers include the
commercially available terephthalates such as Eastman 168TM; OXSOFT
GPOTM; and LGFLEX GLTM 300 (bis(2-ethylhexyl) terephthalate).
Particularly useful examples of plasticizers include the
commercially available di-benzoate plasticizer mixtures such as:
BENZOFLEX 988; BENZOFLEX 2088; KFLEX 500; and SANTICIZER 9000
series.
[0065] The polymer composition comprising a thermoplastic polymer
and at least one plasticizer blend described herein prepared
according to the present invention may further contain additives to
optimize the chemical, mechanical or processing properties, said
additives being more particularly selected from the group
consisting of fillers, such as calcium carbonate, titanium dioxide
or silica, pigments, thermal stabilizers, antioxidants, UV
stabilizers, lubricating or slip agents, flame retardants,
antistatic agents, biocides, impact modifiers, blowing agents,
(polymeric) processing aids, viscosity depressants or regulators
such as thickener and thinners, antifogging agents, optical
brighteners, etc.
[0066] Thermal stabilizers useful herein include all customary
polymer stabilizers, especially PVC stabilizers in solid or liquid
form, examples are those based on Ca/Zn, Ba/Zn, Pb, Sn or on
organic compounds (OBS), and also acid-binding phyllosilicates such
as hydrotalcite. The polymer compositions to be used according to
the present invention may have a thermal stabilizer content of 0.5
to 10, preferably 0.8 to 5 and more preferably 1.0 to 4 wt %, based
upon the weight of the polymer composition.
[0067] It is likewise possible to use co-stabilizers with
plasticizing effect in the polymer composition comprising a
thermoplastic polymer and at least one plasticizer blend as
described herein, in particular epoxidized vegetable oils, such as
epoxidized linseed oil or epoxidized soya oil.
[0068] Antioxidants are also useful in the polymer composition
comprising a thermoplastic polymer and at least one plasticizer
blend described herein and can include sterically hindered
amines--known as HALS stabilizers, sterically hindered phenols,
such as TOPANOL CA, phosphites, UV absorbers, e.g.,
hydroxybenzophenones, hydroxyphenylbenzotriazoles and/or aromatic
amines. Suitable antioxidants for use in the compositions of the
present invention are also described for example in "Handbook of
Vinyl Formulating" (editor: R. F. Grossman; J. Wiley & Sons;
New Jersey (US) 2008). The level of antioxidants in the mixtures of
the present invention is typically not more than 10 phr, preferably
not more than 8 phr, more preferably not more than 6 phr and even
more preferably between 0.01 and 5 phr (phr=parts per hundred parts
of polymer composition).
[0069] Organic and inorganic pigments can be also used in the
polymer composition comprising a thermoplastic polymer and at least
one plasticizer blend as described herein. The level of pigments in
the compositions to be used according to the present invention is
typically not more than 10 phr, preferably in the range from 0.01
to 5 phr and more preferably in the range from 0.1 to 3 phr.
Examples of useful inorganic pigments are TiO.sub.2, CdS,
CoO/Al.sub.2O.sub.3, Cr.sub.2O.sub.3. Examples of useful organic
pigments are for example azo dyes, phthalocyanine pigments,
dioxazine pigments and also aniline pigments.
[0070] The polymer composition comprising a thermoplastic polymer
and at least one plasticizer blend described herein may contain one
or more filler, including mineral and/or synthetic and/or natural,
organic and/or inorganic materials, for example, calcium oxide,
magnesium oxide, calcium carbonate, barium sulphate, silicon
dioxide, phyllosilicate, carbon black, bitumen, wood (e.g.
pulverized, as pellets, micropellets, fibers, etc.), paper, natural
and/or synthetic fibers, glass, etc.
[0071] The compositions described herein can be produced in various
ways. In general, however, the composition is produced by
intensively mixing all components in a suitable mixing container at
elevated temperatures. The plastic pellet or powder (typically
suspension PVC, microsuspension PVC or emulsion PVC) is typically
mixed mechanically, i.e., for example in fluid mixers, turbomixers,
trough mixers or belt screw mixers with the plasticizer blend and
the other components at temperatures in the range from 60.degree.
C. to 140.degree. C., preferably in the range from 80.degree. C. to
100.degree. C. The components may be added simultaneously or,
preferably, in succession (see also E. J. Wickson "Handbook of PVC
Formulating", John Wiley and Sons, 1993, pp. 747 ff). The polymer
composition of PVC, plasticizer and other additive as described
above (e.g., the PVC compound or the PVC paste) is subsequently
sent to the appropriate thermoplastic molding processes for
producing the finished or semi-finished article, optionally a
pelletizing step is interposed.
[0072] The polymer compositions (e.g., the PVC compound or the PVC
paste) are particularly useful for production of garden hoses,
pipes, and medical tubing, floor coverings, flooring tiles,
underbody car coating and sealants, latex and caulk, films,
sheeting, roofing, or roofing webs, pool liners, building
protection foils, upholstery, and cable filling compound, sheathing
and wire insulation, particularly wire and cable coating, coated
textiles and wall coverings.
[0073] The plasticizers of the invention are useful across the
range of plasticized polyvinyl chloride materials. The plasticizers
of the invention are useful in the production of semi-rigid
polyvinyl chloride compositions which typically contain from 10 to
40 phr, preferably 15 to 35 phr, more preferably 20 to 30 phr of
plasticizer (phr=parts per hundred parts PVC); flexible polyvinyl
chloride compositions which typically contain from 40 to 60 phr,
preferably 44 to 56 phr, more preferably from 48 to 52 phr
plasticizer; and highly flexible compositions which typically
contain from 70 to 110 phr, preferably 80 to 100 phr, more
preferably 90 to 100 phr of plasticizer.
[0074] One widespread use of polyvinyl chloride is as a plastisol.
A plastisol is a fluid or a paste consisting of a mixture of
emulsion polyvinyl chloride and a plasticizer optionally containing
various additives, such as those described above. A plastisol is
used to produce one or more layers of polyvinyl chloride which are
coated, pre-gelled, literally build-up and fused to produce
coherent articles of flexible polyvinyl chloride. Plastisols are
useful in the production of flooring, tents, tarpaulins, coated
fabrics such as automobile upholstery, in car underbody coatings,
in mouldings and other consumer products. Plastisols are also used
in footwear, fabric coating, toys, vinyl glove, and wallpaper.
Plastisols typically contain 40 to 200 phr, more typically 50 to
150 phr, more typically 70 to 120 phr, more typically 90 to 110 phr
of plasticizer.
[0075] In a preferred embodiment of the invention, one or more
(such as two or three) plasticizers produced herein are combined
with a polymer such as PVC to form a PVC compound (typically made
from suspension PVC) or a PVC paste (typically made from an
emulsion PVC). A particularly useful PVC in the PVC compound or
paste is one having a K value above 70. Particularly preferred PVC
compounds or paste comprise: 20 to 150 phr (parts per hundred of
resin) plasticizer(s), more preferably 30 to 70 phr and/or 0.5 to
15 phr stabilizer(s), and/or 1 to 30 phr, preferably 15 to 30 phr,
filler(s), even more preferably the filler is calcium carbonate and
the stabilizer is a calcium/zinc stabilizer. The above combination
is useful in wire and cable coatings, particularly automobile wire
and cable coating and or building wire insulation.
[0076] The following examples are meant to illustrate the present
disclosure and inventive processes, and provide where appropriate,
a comparison with other methods, including the products produced
thereby. Numerous modifications and variations are possible and it
is to be understood that within the scope of the appended claims,
the disclosure can be practiced otherwise than as specifically
described herein.
EXAMPLES
[0077] Several esters of 1- and 2-naphthoic acid were synthesized
using the reaction scheme shown below and then compared with known
commercial plasticizers including diisononyl phthalate (JAYFLEX
DINP, PALATINOL N, VESTINOL 9), dioctyl terephthalate (DOTP,
EASTMAN 168), and 1,2-cyclohexane dicarboxylic acid diisononyl
ester (Hexamoll DINCH). In particular, the synthetic route for the
preparation of material used for testing below was a one pot
reaction starting from commercially available naphthoic acids with
a titanium catalyst. In the route below, TIOT is titanium
iso-octyl.
##STR00025##
[0078] The naphthoic acid mono-ester plasticizers were then blended
with PVC for plasticizer performance testing according the general
procedure shown below. As shown in Table 2 below, compounds were
blended with PVC and tested for volatility and viscosity. The
dodecyl-2-naphthoate (Inventive Example 4) in this preliminary
screening showed promising results compared to other general
purpose plasticizers like DINP and DOTP.
General Procedure
[0079] A 4.5 g portion of the ester sample was weighed into an
ERLENMEYER flask which had previously been rinsed with uninhibited
tetrahydrofuran (THF) to remove dust. A 0.63 g portion of a 70:30
by weight solid mixture of powdered DRAPEX 6.8 (Crompton
Corporation) and MARK 4716 (Chemtura USA Corporation) stabilizers
were then added along with a stir bar. The solids were dissolved in
90 mL uninhibited THF. OXY VINYLS 240F PVC (9.0 g) was added in
powdered form and the contents of the flask were stirred overnight
at room temperature until dissolution of the PVC was complete (a
PVC solution for preparation of an unplasticized comparative sample
was prepared using an identical amount of stabilizer, 100 mL
solvent, and 13.5 g PVC). The clear solution was poured evenly into
a clean, flat aluminum paint can lid (previously rinsed with
inhibitor-free THF to remove dust) of dimensions 7.5'' diameter and
0.5'' depth. The lid was placed into an oven at 60.degree. C. for 2
hours with a moderate nitrogen purge. The pan was removed from the
oven and allowed to cool for about 5 minutes. The resultant clear
film was carefully peeled off the aluminum, flipped over, and
placed back evenly into the pan. The pan was then placed in a
vacuum oven at 70.degree. C. overnight to remove any residual THF.
The dry, flexible, almost colorless film was carefully peeled away
again and exhibited no oiliness or inhomogeneity. The film was then
cut into small pieces to be used for preparation of test bars by
compression molding (size of pieces was similar to the hole
dimensions of the mold plate). The film pieces were stacked into
the holes of a multi-hole steel mold plate pre-heated to
170.degree. C. and having hole dimensions 20 mm.times.12.8
mm.times.1.8 mm (ASTM D1693-95 dimensions). The mold plate was
pressed in a PHI Company QL-433-6-M2 model hydraulic press equipped
with separate heating and cooling platforms. The upper and lower
press plates were covered in TEFLON-coated aluminum foil and the
following multistage press procedure was used at 170.degree. C.
with no release between stages: (1) 3 minutes with 1-2 ton
overpressure; (2) 1 minute at 10 tons; (3) 1 minute at 20 tons; (4)
1 minute at 30 tons; (5) 3 additional minutes at 30 tons; (6)
release and 3 minutes in the cooling stage of the press (7.degree.
C.) at 30 tons. A knockout tool was then used to remove the sample
bars with minimal flexion.
[0080] The data included herein show that effective aromatic
plasticizers can be made from the methods disclosed herein.
[0081] Test procedures for measuring the performance properties of
the plasticizers in Table 2 below were as follows:
[0082] 1. Volatility was measured according to 98.degree. C. weight
loss comparison of PVC bars plasticized with esters versus PVC bars
plasticized with a commercial plasticizer. More particularly, two
each of the PVC sample bars were placed in aluminum weighing pans
and placed inside a convection oven at 98.degree. C. Initial weight
measurements of the hot bars and measurements taken at specified
time intervals were recorded and results were averaged between the
bars.
[0083] 2. Viscosity was measured versus shear rate and the value
was taken at 334 .sup.s-1.
[0084] As can be seen, the inventive naphthoic acid mono-ester
examples in the tables above provide a good combination of
volatility, and viscosity properties. In addition, four of the
inventive naphthoic acid mono-ester examples (Inventive examples 1,
2, 4, and 7 in Table 2) provided particularly outstanding
properties. All four provided a combination of outstanding
volatility (less than or equal to 4.5 wt %) and viscosity. These
four inventive naphthoic acid mono-ester plasticizers have a
viscosity at 334 sec.sup.-1 ranging from 33 to 57 centipoise.
Comparative data for the commercial plasticizers JAYFLEX DINP
(ExxonMobil Chemical Company), DOTP and Hexamoll DINCH (di-isonyl
cyclohexanoate from BASF) is also included.
TABLE-US-00002 TABLE 2 Viscosity Vola- (cp @ Examples Description
Structure tility 334s-1) Comparative Example 1 DINP ##STR00026##
2.6 81 Comparative Example 2 DOTP ##STR00027## 2.7 86 Comparative
Example 3 DINCH ##STR00028## 4 51 Comparative Example 4
Didecylnaphthalene- 1,8-dicarboxylate ##STR00029## 0.4 75 Inventive
Example 1 Decyl-2-naphtoate ##STR00030## 3.9 50 Inventive Example 2
Decyl-1-naphtoate ##STR00031## 4.5 33 Inventive Example 3 Decyl
5,6,7,8- tetrahydronapthalene- 2-dicarboxylate ##STR00032## 4.2 45
Comparative Example 5 Dibutyl naphthalene 1,8-dicarboxylate
##STR00033## 4.1 805 Comparative Example 6 Dibutyl naphthalene-
1,8-dicarboylate ##STR00034## 1.8 473 Inventive Example 4
Dodecyl-2- naphthoate ##STR00035## 2.5 57 Inventive Example 5 Exxal
10-2- naphthoate ##STR00036## 5.2 84 Inventive Example 6 Exxal
13-2- naphthoate ##STR00037## 3.0 197 Inventive Example 7
Dodecyl-1- naphthoate ##STR00038## 2.3 41 Inventive Example 8 Exxal
13-1- naphthoate ##STR00039## 3.5 106 ##STR00040##
[0085] Additional properties of the plasticizers are provided in
Tables 3 and 4 below. Table 3 provides comparisons of volatilities
(TGA weight loss %) and glass transition temperatures (Tg) of the
different ester fractions. The Tg of the polymer compositions was
determined using Dynamic Mechanical Thermal Analysis ("DMTA"). The
Tg of the neat plasticizers was determined using Differential
Scanning calorimetry ("DSC"). The Tg's given in Table 4 are
midpoints of the second heats obtained by Differential Scanning
calorimetry (DSC) using a TA Instruments Q2000 calorimeter fitted
with a liquid N.sub.2 cooling accessory. Samples about 10 mg in
size were loaded at room temperature (about 22.degree. C.), heated
to 100.degree. C. at 10.degree. C./min, maintained at 100.degree.
C. for one minute, cooled to -90.degree. C. at 10.degree. C./min,
maintained at -90.degree. C. for one minute, and then reheated at
10.degree. C./min. The Tg was recorded during the second heating.
Thermogravimetric Analysis (TGA) was conducted on the neat esters
using a TA Instruments TGA5000. Samples about 10 mg in size were
loaded at room temperature (about 22.degree. C.) and then heated at
10.degree. C./min in an argon atmosphere, and weight loss was
recorded at 220.degree. C.
TABLE-US-00003 TABLE 3 1,2-naphtoate esters: neat properties TGA wt
Viscosity/density loss % @ Tg/Pour pt @20.degree. C. 220.degree. C.
(.degree. C.) (mPa s/g/cm3) Comparative DINP 3.2 (*) -80/-51
95/0.974 Example 1 Comparative DOTP 1.9 -36/-57 86/0.984 Example 2
Comparative DINCH 2.6 -90/-57 50/0.950 Example 3 Inventive Exxal
7-2- -- /-50 44/1.0276 Example 9 naphthoate Inventive Exxal 10-2-
8.4 -69/-43 93/1.007 Example 10 naphthoate Inventive Exxal 13-2-
/-38 190/0.9887 Example 11 naphthoate Inventive Exxal 10-1- 12.6
-74/-52 47/1.009 Example 12 naphthoate Inventive Exxal 13-1- 3.6
-67/-43 101/0.993 Example 13 naphthoate
[0086] The solution temperature of a plasticizer is the temperature
at which a set amount of PVC gets dissolved in a set amount of
plasticizer. The solution temperature is not only influenced by the
plasticizer type but also by the PVC resin type and in particular
the K-10 Value (DIN 53408 Testing of Plastics; Determination of
Solubility Temperature of Polyvinyl Chloride (PVC) in Plasticizers
(1967 Jun. 1)). A lower solution temperature indicates a
plasticizer that will gel or fuse faster. The plasticizers of the
present invention exhibit similar or substantially lower solution
temperatures than DINP (Table 4).
[0087] Additionally, the plasticizers of the present invention made
with branched alcohols exhibit very low pour points. Plasticizers
based on linear alcohols tend to have high pour points, as shown in
Inventive Example 15. Mixing linear and branched alcohol based
naphthoates can lower the pour point of the resulting blend.
TABLE-US-00004 TABLE 4 C12-13 C13-15 2-naphthoate 2-naphthoate C10
C13 C10 C13 Inventive Inventive DINP 1-naphthoate 1-naphthoate
2-naphthoate 2-naphthoate Example 14 Example 15 Neat plasticizer 95
47 101 93 190 78 81 viscosity, mPa s ASTM D7042 Solution 129 106
118 109 120 125 129 Temperature, .degree. C. DIN 53408 Pour Point,
.degree. C. -51 -52 -43 -43 -38 -20 0 ASTM D5950
[0088] Flow properties of plastisols are important in spread
coating processes like wall coverings, floorings, or coated
fabrics. In general, low viscosity is desired at high shear rate.
PVC plastisol formulations, prepared by mixing in a Hobart mixer,
are provided in Table 5 below. The plastisols were prepared with
100 parts of PVC, 40 parts per hundred of PVC of plasticizer, and 2
parts per hundred of PVC of a conventional CaZn stabilizer.
Formulation T52 contained DINP as a plasticizer for comparative
purposes.
TABLE-US-00005 TABLE 5 Example T52 T53 T54 T55 T57 PVC 100 100 100
100 100 DINP 40 Isodecyl 2-naphthoate (Exxal 10) 40 (Inventive
Example 10) Isodecyl 1-naphthoate (Exxal 10) 40 (Inventive Example
12) Isotridecyl 1-naphthoate (Exxal 13) 40 (Inventive Example 13)
Isodecyl 2-naphthoate (Exxal 10) 40 (Inventive Example) Lankromark
LZC525 2 2 2 2 2
[0089] The initial viscosity of the PVC plastisol formulations was
evaluated at low shear by measuring the Brookfield viscosity after
two hours at room temperature (about 22.degree. C.) and 20 rpm. The
plastisol viscosity stability was also evaluated by measuring the
viscosity after one and two days. Results are shown in Table 6
below.
TABLE-US-00006 TABLE 6 Brookfield viscosity RT and 20 rpm mPa s T52
T53 T54 T55 T57 2 hours 7700 7700 4150 11000 7600 1 day 5800 6900
4100 8000 8150 2 days 6900 9050 5300 9150 --
[0090] Plastisol formulations based on isodecyl-2-napthoate (T54)
exhibit similar initial Brookfield viscosity to DINP-based
plastisols, while plastisol formulations based on
isodecyl-1-napthoate (T54) exhibit lower Brookfield viscosity than
DINP-based plastisol formulations. Isodecyl-1-napthoate based
plastisol formulations (T54) exhibit good viscosity stability over
time. The viscosity of alkyl 1-naphthoate plastisol formulations
(T55) increases with the alcohol carbon number.
[0091] An .sup.1H NMR spectrum of Inventive Sample 4,
dodecyl-2-napththoate, is provided in FIG. 1. Additionally, a
.sup.13C NMR spectrum of Inventive Sample 4 is provided in FIG.
2.
[0092] Plastisols applied on a substrate (coating, dipping,
gun-spraying) undergo a shear stress and exhibit shear thinning
behavior. Plastisol viscosity under shear rate after one day
storage at room temperature (about 22.degree. C.) was assessed on
several of the inventive examples and results are provided in FIG.
3, confirming the interesting rheology of the 1-naphthoate
esters.
[0093] When processing plastisols, the gelling energy is worked
only by heat-transfer. The higher the processing temperature
needed, the longer the time needed to achieve plastisol gelation.
Processors require plasticizers and plastisols with low processing
temperature (faster gelling). The rate of plastisol storage modulus
increase (G' storage or elastic modulus) gives an indication of the
plasticizer's fast gelling ability. Gelation behavior, from initial
gelation and final gelation up to fusion, was obtained for the
plastisol formulations and the gelation curve is provided in FIG.
4.
[0094] This gelation curve was obtained using dynamic mechanical
analysis (DMA). Specifically, the curve was measured using an Anton
Paar PHYSICA MCR 101 Rheometer equipped with the plate/plate
measuring geometry. The settings were PP 50--frequency 1
Hz--amplitude 0.1%--heating rate 10.degree. C./min--start
temperature 20.degree. C.--gap: 1 mm--end temperature 195.degree.
C., Normal force=0 Newton.
[0095] When gelation begins, both moduli (G', G'') and complex
viscosity (.eta.*) rise sharply. The plasticizer begins to interact
with the outer part of the PVC resin particles. When the gelation
stage is completed, both moduli (G', G'') and complex viscosity
(.eta.*) reach a maximum. The whole plasticizer has been absorbed
by the PVC resin. When fusion takes place, the elastic and viscous
moduli drop off and melting of the crystalline portion of the PVC
occurs.
[0096] The gelation curves in FIG. 4 highlight the superior
gelation performance of the plasticizers of the invention compared
to DINP. The increased rate of the G' (storage modulus) as a
function of the temperature of the naphthoate based formulations
occurs at a much lower temperature for the inventive formulations
than for DINP. The maximum level achieved by the storage modulus is
also much higher than DINP, indicating a higher elasticity
maintained during initial and final gelation.
[0097] Table 7 provides three temperatures measured during the
plastisol gelation process. Dynamic mechanical analysis of the
inventive plastisol formulations as they were heated to final
fusion gave initial and final gelation temperatures that are lower
than the comparative example based on DINP. All tested naphthoate
plasticizers were found to be faster fusing plasticizers with lower
initial and final gelation temperatures.
TABLE-US-00007 TABLE 7 Plastisol gelation and figure storage
modulus as a function of temperature. Temp. (.degree. C.) T52 T53
T54 T55 Min gap 92 83 82 87 G' at 10.sup.4 Pa 105 91 88 97 G' at
10.sup.5 Pa 120 95 92 102
[0098] Mechanical properties of molded plastisols (hardness and
Clash-Berg) were obtained. Pads were prepared from films obtained
by curing plastisols in a Werner Mathis oven (setting 170.degree.
C./1 min @ 1500 rpm). Films were then pressed and molded at
180.degree. C. for 15 min. Shore A and D hardness (ASTM D 2240-86)
and cold flexibility performance were measured and are provided in
Table 8. Naphthoate esters can offer a wide range of plasticizing
efficiency, showing various Shore A or D hardness levels at the
same plasticizer concentration. A C10 1-naphthoate is more
efficient than DINP while a C13 based 1-naphthoate is less
efficient. A C10 2-naphthoate exhibits similar plasticizing
efficiency to DINP.
TABLE-US-00008 TABLE 8 Properties T52 T53 T54 T55 Shore A >90
>90 87 >90 Shore D 38 39 35 42 Clash-Berg T (.degree. C.) -13
-4 -5 -7
[0099] Flexible PVC dumbbells made from the formulations shown in
Table 9 were evaluated for their stiffness at low temperature. The
formulations were prepared in a low speed Hobart mixer. The wet
blend was processed into a flexible sheet by milling on a Dr.
Collins roll mill at 165.degree. C. for 6 minutes. The milled sheet
was removed from the roll mill, cooled to room temperature, and
then portions of this product were pressed to test specimens of
various thicknesses at 170.degree. C. for 15 minutes. After
cooling, the test specimens were removed from the molds, and
conditioned for 7 days at 22.degree. C. and 50% relative humidity.
The Shore A hardness (ASTM D 2240-86) and tensile properties (30
mil test specimens, Type C die)) were measured and are reported in
Table 10 below. The naphthoate-based formulations were slightly
stiffer than the DINP-based formulation. Additional properties of
the formulations before and after aging are provided in Table
11.
TABLE-US-00009 TABLE 9 Example T1 T2 T3 T4 PVC (Solvin 271PC) 100
100 100 100 DINP 50 Isodecyl 2-naphthoate (Exxal 10) 50 Isodecyl
1-naphthoate (Exxal 10) 50 Isotridecyl 1-naphthoate (Exxal 13) 50
CaCO.sub.3 60 60 60 60 Baeropan 81/5 3 3 3 3
TABLE-US-00010 TABLE 10 T1 T2 T4 Shore A before aging 92 89 92
Shore D before aging 42 37 42 Shore A after aging 10 days @
100.degree. C. 91 89 91 Shore D after aging 10 days @ 100.degree.
C. 40 38 42
TABLE-US-00011 TABLE 11 Mechanical properties before and after
aging 10 days @100.degree. C. natural ventilation). T1 T2 T4 Before
aging Force Mod-100% 13.1 12.2 13.6 Stress at Break (N/mm2) 18.7
19.6 19.6 Elongation at Break (%) 324 316 314 After aging Force
Mod-100% 13.7 14.4 14.5 Stress at Break (N/mm2) 18.8 19.0 19.0
Elongation at Break (%) 315 280 298
[0100] The lower solution temperatures (higher solvency) of the
inventive plasticizers translates into short dry blending time
compared to DINP, as can be seen in Table 12 below and FIG. 5.
TABLE-US-00012 TABLE 12 T1 T2 T4 Dry Blending Time (s) 192 90 142
Solution temperature (.degree. C.) 129 106 118
[0101] Additional information on the test methods used herein is
provided below:
[0102] 1) Brookfield Viscosity: ASTM D 1824--Standard test method
is used for apparent viscosity of plastisols and organosols at low
shear rates using a Brookfield viscometer, spindle RV 1 to 7.
[0103] 2) Plasticizer Neat Viscosity and Density: ASTM D
7042--Standard Test Method is used for Dynamic Viscosity and
Density of Liquids by Stabinger Viscometer (and the Calculation of
Kinematic Viscosity).
[0104] 3) Low Temperature Flexibility: Clash-Berg measurement is
used and based upon ASTM D 1043-84--Stiffness properties of
plastics as a function of temperature by means of a torsion
test.
[0105] 4) Neat Plasticizer Volatility: Neat plasticizer weight loss
(in wt %) is measured on neat plasticizer after heating plasticizer
for 24 h at 115.degree. C. in a forced ventilated oven (>160 air
renewal/hour).
[0106] 5) Solution Temperature: The solution temperature of
plasticizers is defined as the temperature at which a set amount of
PVC gets dissolved in a set amount of plasticizer. The solution
temperature is not only influenced by the plasticizer type but also
by the PVC resin type and in particular the K-10 Value (DIN 53408
Testing of Plastics; Determination of Solubility Temperature of
Polyvinyl Chloride (PVC) in Plasticizers (1967 Jun. 1)).
[0107] 6) Mechanical properties (original) were obtained from
samples in a Zwick tensile tester measuring the modulus at 100%
extension, the ultimate tensile strength in psi and ultimate
elongation in % according to ASTM D 638. The same mechanical
properties were measured on dumbbells that had been aged at
100.degree. C. for 10 days, with airflow of +-150 air
changes/hr.
[0108] 7) Dry blending time was measured by using a planetary mixer
P600 from Brabender. Planetary mixer are used for testing the
plasticizer absorption rate of PVC powders or the pour ability of
dry blends. A special rotor runs in a planetary motion in the mixer
bowl while a revolving scrapper prevents the PVC mix from sticking
to the mixer wall. PVC, CaCO3 and stabilizer are mixed first while
heating the bowl to the set temperature. Plasticizer is than added
after +-5 min. Torque and absorption time are recorded.
[0109] The meanings of terms used herein shall take their ordinary
meaning in the art; reference shall be taken, in particular, to
Handbook of Petroleum Refining Processes, Third Edition, Robert A.
Meyers, Editor, McGraw-Hill (2004). In addition, all patents and
patent applications, test procedures (such as ASTM methods), and
other documents cited herein are fully incorporated by reference to
the extent such disclosure is not inconsistent with this disclosure
and for all jurisdictions in which such incorporation is permitted.
Also, when numerical lower limits and numerical upper limits are
listed herein, ranges from any lower limit to any upper limit are
contemplated.
[0110] The disclosure has been described above with reference to
numerous embodiments and specific examples. Many variations will
suggest themselves to those skilled in this art in light of the
above detailed description. All such obvious variations are within
the full intended scope of the appended claims.
* * * * *