U.S. patent application number 11/040880 was filed with the patent office on 2005-06-09 for fluoropolymer blends and multilayer articles.
This patent application is currently assigned to 3M Innovative Properties Company. Invention is credited to Bilbrey, David B., Fukushi, Tatsuo, Haak, Christopher A., Hine, Andrew M., Jing, Naiyong, Molnar, Attila, Muggli, Mark W., Spurgeon, Kathryn M..
Application Number | 20050124717 11/040880 |
Document ID | / |
Family ID | 29214883 |
Filed Date | 2005-06-09 |
United States Patent
Application |
20050124717 |
Kind Code |
A1 |
Jing, Naiyong ; et
al. |
June 9, 2005 |
Fluoropolymer blends and multilayer articles
Abstract
Disclosed are various fluoropolymer blend combinations and
multilayer articles comprising a blend in a first layer and a
second layer comprising a polymer bonded to the first layer. The
invention also provides an article comprising a first layer
comprising a blend of two or more fluoropolymers, and a second
layer bonded to the first layer, the second layer comprising a
partially-fluorinated thermoplastic polymer, a perfluorinated
thermoplastic polymer, or a combination thereof. The invention also
provides an article comprising a first layer comprising a blend of
two or more fluoropolymers, at least one of which comprises a
partially-fluorinated thermoplastic polymer, and optionally at
least one perhalogenated polymer, and a second layer bonded to the
first layer, the second layer comprising an at least
partially-fluorinated thermoplastic polymer. The invention also
provides processes for preparing blended fluoropolymers and
multilayer articles comprising a fluoropolymer layer.
Inventors: |
Jing, Naiyong; (Woodbury,
MN) ; Fukushi, Tatsuo; (Woodbury, MN) ;
Molnar, Attila; (Vadnais Heights, MN) ; Bilbrey,
David B.; (Woodbury, MN) ; Muggli, Mark W.;
(West St. Paul, MN) ; Hine, Andrew M.; (St. Paul,
MN) ; Spurgeon, Kathryn M.; (River Falls, WI)
; Haak, Christopher A.; (Oakdale, MN) |
Correspondence
Address: |
3M INNOVATIVE PROPERTIES COMPANY
PO BOX 33427
ST. PAUL
MN
55133-3427
US
|
Assignee: |
3M Innovative Properties
Company
|
Family ID: |
29214883 |
Appl. No.: |
11/040880 |
Filed: |
January 21, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11040880 |
Jan 21, 2005 |
|
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10125936 |
Apr 18, 2002 |
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6849314 |
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Current U.S.
Class: |
522/156 |
Current CPC
Class: |
Y10T 428/1393 20150115;
Y10T 428/31544 20150401; Y10T 428/31678 20150401; C08L 2666/04
20130101; C08L 27/16 20130101; C08L 2205/02 20130101; C08L 2666/04
20130101; B32B 27/28 20130101; C08L 27/18 20130101; Y10T 428/3154
20150401; C08L 27/18 20130101; B32B 27/08 20130101; C08L 27/16
20130101 |
Class at
Publication: |
522/156 |
International
Class: |
C08J 003/18 |
Claims
We claim:
1. A fluoropolymer composition comprising a partially
fluorinated-thermoplastic polymer in a blend with at least one
additional component selected from: (i) a perfluorothermoplastic,
wherein the partially fluorinated-thermoplastic is substantially
non-vinylidene fluoride containing; (ii) two or more different
perfluoropolymers, one or more of which may be thermoplastic; (iii)
a different partially-fluorinated thermoplastic polymer, wherein
the partially fluorinated-thermoplastic polymers have
interpolymerized units derived from a substantial amount of
vinylidene fluoride; (iv) two different partially-fluorinated
thermoplastic polymers.
2. A blend according to claim 1 wherein the partially
fluorinated-thermoplastic is derived from a combination of
interpolymeiized units of tetrafluoroethylene, hexafluoropropylene,
perfluoro alkyl or alkoxy vinyl ethers, and nonfluorinated
olefins.
3. A blend according to claim 1 wherein the perfluorothermoplastic
is selected from FEP, PFA, or a combination thereof.
4. The blend of claim 1 further comprising a fluoroelastomer and/or
a perfluoroelastomer.
5. A blend according to claim 1 having at least two
partially-fluorinated thermoplastic polymers with interpolymerized
units derived from a substantial amount of vinylidene fluoride and
further comprising a perfluoropolymer derived from interpolymerized
units of two or more of tetrafluoroethylene, hexafluoropropylene,
and perfluoro alkyl or alkoxy vinyl ethers.
6. A blend according to claim 1 having at least two
partially-fluorinated thermoplastic polymers with interpolymerized
units derived from a substantial amount of vinylidene fluoride and
wherein one or more of the vinylidene fluoride-containing
thermoplastic copolymer(s) further comprise(s) interpolymerized
units derived from tetrafluoroethylene, hexafluoropropylene, and
optionally a perfluoro alkyl or alkoxy vinyl ether.
7. A blend according to claim 1 having at least two
partially-fluorinated thermoplastic polymers with interpolymerized
units derived from a substantial amount of vinylidene fluoride and
wherein one of the thermoplastic polymers has a vinylidene fluoride
content between about 3 and 30 weight percent and wherein a second
of said thermoplastic polymers has a vinylidene fluoride content
between about 20 and 60 weight percent.
8. A blend according to claim 1 having at least three
partially-fluorinated thermoplastic polymers wherein at least one
polymer is derived from a combination of interpolymerized units of
tetrafluoroethylene, hexafluoropropylene, vinylidene fluoride,
perfluoro alkyl or alkoxy vinyl ethers, and/or nonfluorinated
olefins.
9. A blend according to claim 1 wherein one or more polymer(s)
further comprises interpolymerized units of according to the
formula: --CF.sub.2--CF(X')--, wherein each X' is independently Cl,
Br, R.sub.f, O(R.sub.fO).sub.aR.sub.f, wherein each R.sub.f is
independently a C.sub.1-C.sub.10 perfluoroalkyl group; or a
perfluorinated polymer comprising interpolymerized units of Formula
II: 2wherein each Y is independently a bond, O, or CF.sub.2; each Z
is independently F or R.sub.f wherein each R.sub.f is independently
a C.sub.1-C.sub.10 perfluoroalkyl group; a is 0-20; and n is
0-3.
10. An article comprising a blend according to claim 1.
11. A polymer composition comprising a blend of a first polymer
having a surface energy below about 20 mJ/m.sup.2 and a second
polymer having a surface energy having below about 25 mJ/m.sup.2,
wherein the difference of the surface energy between the first
polymer and the second polymer is from 1 mJ/m.sup.2 to 5
mJ/m.sup.2.
12. An article comprising the polymer composition of claim 11.
13. The polymer composition of claim 9 wherein the first polymer is
provided in a layer adjacent to a layer of the second polymer.
14. An article comprising the layered polymer composition of claim
13.
15. A permeation resistant fluoropolymer composition comprising: a)
a perfluoropolymer; and b) from about 5 to about 50 weight percent,
based on the fluoropolymer composition, of a partially-fluorinated
polymer; wherein the fluoropolymer composition has a Permeation
Constant below about 50% greater than the perfluoropolymer
alone.
16. The composition of claim 15 wherein the composition has a
Permeation Constant below about 25% greater than the
perfluoropolymer alone.
17. The composition of claim 15 wherein the perfluoropolymer is FEP
or PFA.
18. The composition of claim 15 wherein the partially-fluorinated
polymer is a copolymer derived from interpolymerized units of
tetrafluoroethylene, hexafluoropropylene, and vinylidene fluoride,
and optionally a perfluoro alkyl or alkoxy vinyl ether.
19. An article comprising the composition of claim 15.
20. A method of making a fluoropolymer composition according to
claim 1 comprising blending a partially fluorinated-thermoplastic
polymer in a blend with at least one additional component selected
from (i) a perfluorothermoplastic, wherein the partially
fluorinated-thermoplastic is substantially non-vinylidene fluoride
containing; (ii) two or more different perfluoropolymers, one or
more of which may be thermoplastic; (iii) a different
partially-fluorinated thermoplastic polymer, wherein the partially
fluorinated-thermoplastic polymers have interpolymerized units
derived from a substantial amount of vinylidene fluoride; and (iv)
two different partially-fluorinated thermoplastic polymers.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of U.S. Ser. No.
10/125,936, filed Apr. 18, 2002, now allowed, the disclosure of
which is herein incorporated by reference.
TECHNICAL FIELD
[0002] This invention relates to fluoropolymer blends, an assembly
of fluoropolymers useful in sheets which may be multi-layered, a
hose such as for conveying fuels or chemicals, and the like, and
processes for preparing multilayer articles such as tubing.
BACKGROUND
[0003] Blending polymers is a simple and effective way to develop a
new polymer composition possessing properties which may not be
available in a single known polymer or which would require
time-consuming and expensive development of an entirely new
polymer. Thus, polymer blends often are used to produce a
composition having some of the desired mechanical, Theological, and
adhesion properties found in the individual polymers used in the
blend.
[0004] Fluoroplastics are used due to their properties, e.g.,
chemical resistance and low fuel permeation. Automotive
applications, such as fuel hoses, demand lower and lower fuel
permeation to minimize emissions and meet stronger environmental
standards. These applications demand fluoropolymers. Thin layers of
fluoropolymers often are used in combination with other materials,
which provide resilience, strength, durability, and other desired
properties in a composite. However, fluoropolymers are known to be
difficult to bond. A variety of methods have been used to promote
adhesion between fluoropolymers and non-fluoropolymers as well as
between two fluoropolymers such as THV and FKM. These methods
include treating the surface of one or both of the layers, using
blends of two polymers such as a polyamide with a THV, mixing a
polyamide and a grafted fluoropolymer having polar functionality,
using tie layers, and using adhesives.
SUMMARY
[0005] Briefly, the present invention provides a fluoropolymer
comprising a blend of a substantially non-vinylidene fluoride
containing partially fluorinated-thermoplastic and a
perfluorothermoplastic. In another aspect, the present invention
provides a fluoropolymer comprising a blend of two or more
perfluoropolymers and a partially fluorinated-thermoplasti- c
polymer. In another aspect, the present invention provides a
fluoropolymer comprising a blend of two or more different
partially-fluorinated thermoplastic polymers having
interpolymerized units derived from a substantial amount of VDF. In
yet another aspect, the present invention provides a fluoropolymer
comprising a blend of three or more partially-fluorinated
thermoplastic polymers.
[0006] In another aspect, the present invention comprises a blend
of a polymer having a surface energy below about 20 mJ/m.sup.2 and
a polymer having a surface energy having below about 25 mJ/m.sup.2,
wherein the difference of the surface energy between the first
layer and the second layer is from 1 mJ/m.sup.2 to 5
mJ/m.sup.2.
[0007] In another aspect, the present invention comprises a
fluoropolymer composition comprising a perfluoropolymer, and from
about 5 to about 50 weight percent, based on the fluoropolymer
composition, of a partially-fluorinated polymer, wherein the
fluoropolymer composition has a Permeation Constant less than about
25% greater than the perfluoropolymer alone. This composition may
be used in a multilayer article, such as those disclosed
herein.
[0008] In another aspect, the present invention provides an article
comprising a first layer comprising a blend as described in the
preceding paragraphs of this section, and a second layer comprising
a polymer bonded to the first layer.
[0009] In another aspect, the present invention provides an article
comprising a first layer comprising a blend of a partially
fluorinated-thermoplastic and a perfluorothermoplastic, and a
second layer bonded to the first layer, the second layer comprising
a polymer selected from elastomers, polyolefins, and polyamides
lacking pendant amines.
[0010] In another aspect, the present invention provides an article
comprising a first layer comprising a blend of two or more
fluoropolymers, which may be perfluorinated, and a second layer
bonded to the first layer, the second layer comprising a
partially-fluorinated thermoplastic polymer, a perfluorinated
thermoplastic polymer, or a combination thereof.
[0011] In another aspect, the present invention provides an article
comprising a first layer comprising a blend of two or more
fluoropolymers, at least one of which comprises a
partially-fluorinated thermoplastic polymer, and optionally at
least one perhalogenated polymer, and a second layer bonded to the
first layer, the second layer comprising an at least
partially-fluorinated thermoplastic polymer.
[0012] In another aspect, the present invention provides a process
for preparing a layered article comprising providing a first layer
comprising a blend of polymers as described in the summary above,
providing a second layer contacting the first layer, the second
layer comprising an at least partially-fluorinated polymer, and
heating at least one layer and the interface between the layers to
a temperature above the softening point or melting point of at
least one of the layers.
[0013] In still another aspect, the present invention provides a
process for preparing a layered article comprising extruding a
first layer comprising a blend of polymers as described in the
summary above, extruding a second layer comprising an at least
partially-fluorinated polymer on a surface of the first layer, and
wherein said first layer and said second layer are bonded while at
least one layer is above its melting point or softening point.
[0014] As used herein:
[0015] "perhalogenated" means that any carbon-bonded hydrogens are
replaced by halogen atoms such as chlorine or fluorine, and when
all carbon-bonded hydrogens are replaced with fluorine, the term
"perfluorinated" is used;
[0016] "partially fluorinated" means that not all carbon-bonded
hydrogens are replaced by fluorine such that one or more hydrogens
remains, and preferably at least one-fourth of the hydrogen atoms
bonded to carbon atoms are replaced with fluorine atoms;
[0017] "fluorinated thermoplastic" means a fluoropolymer having a
distinct melting point, as distinguished from amorphous materials
such as fluoroelastomers that usually do not have such a melting
point; "thermoplastic elastomer" means a rubber-like material that
can be process like thermoplastic materials, and "substantially
solid" means less than 30% of the volume of a layer is comprised of
enclosed voids or gases such as prevalent in foamed
constructions.
[0018] It is an advantage of the present invention to provide
various fluoropolymer blends, and multilayer articles comprising a
fluoropolymer blend. For example, a multi-layer construction having
a perfluoropolymer as a protecting layer and its blend with a
partially fluorinated polymer as a second layer, and a multi-layer
construction having perfluoropolymer-containing blends as mentioned
above as a protecting layer and partially fluorinated polymer as a
second layer.
[0019] In one aspect, one or more layers in the article of the
invention is substantially solid, containing less than 30% of its
volume comprise of enclosed voids or gases such as prevalent in
foamed constructions. In other embodiments, less than 20%, less
than 10% or even 0% of the volume of a layer comprises enclosed
voids or gases.
[0020] The interlayer adhesion of the inventive constructions is
sufficiently strong to make these constructions suitable for
practical uses. It is an advantage of the present invention to
provide multilayer fluoropolymer articles that include a
fluoropolymer blend in at least one layer, such as sheets, tubing,
hoses, and other shaped articles. These blends also can be used as
tie layers, such as for bonding perfluorinated polymers including
fluorinated ethylene propylene (FEP) and
tetrafluoroethylene-perfluoropropylalkoxy (PFA) to some partially
fluorinated polymers such as those derived from tetrafluoroethylene
(TFE), hexafluoropropylene (HFP), and vinylidene fluoride (VDF),
which enables a plethora of constructions heretofore unknown. In
addition, the invention can be used as a modified perfluorinated
polymer, which can be bonded to a variety of organic and inorganic
substrates. Among the many applications of the invention are:
biomedical devices, electronic materials, and binders (low
dielectric constants and high thermal stability), low surface
energy adhesive tapes, anti-graffiti films, and multi-layer fuel
system hoses and tubes. The mechanical properties of these blends
provide desirable levels of flexibility, tensile strength, and
elongation.
[0021] Other features and advantages of the invention will be
apparent from the following detailed description of the invention
and the claims. The above summary of principles of the disclosure
is not intended to describe each illustrated embodiment or every
implementation of the present disclosure. The following details
more particularly exemplify certain preferred embodiments utilizing
the principles disclosed herein.
DETAILED DESCRIPTION
[0022] The present inventors have discovered that blends of two or
more fluoropolymers in various ratios are visually clear.
Surprisingly, these blends, in particular the partially-fluorinated
polymer blends, can be adhered to notoriously inert fluoropolymer
such as FEP and (tetrafluoroethylene-ethylene) ETFE without any
additional chemical treatments, at the same time they are bondable
to partially fluorinated polymers such as those derived from TFE,
HFP, and VDF, and the like, as well as other partially fluorinated
polymers, which previously were known to bond to organic and
inorganic substrates by tie layer or primer chemistries. The
articles of the invention have excellent interlayer adhesion and
these multi-layer articles remain transparent.
[0023] The invention provides various fluoropolymer blends
including a blend of a substantially non-vinylidene fluoride
containing partially fluorinated-thermoplastic and a
perfluorothermoplastic, a blend of two or more perfluoropolymers
and a partially fluorinated-thermoplastic polymer, a blend of two
or more different partially-fluorinated thermoplastic polymers
having interpolymerized units derived from VDF, and a blend of
three or more partially-fluorinated thermoplastic polymers. In
addition, the invention provides a fluoropolymer composition
comprising a perfluoropolymer, and from about 5 to about 50 weight
percent, based on the fluoropolymer composition,. of a
partially-fluorinated polymer, wherein the fluoropolymer
composition has a Permeation Constant less than about 50% greater
(preferably less than about 25% greater, more preferably less than
about 15% greater) than the perfluoropolymer alone.. In this
aspect, copolymers of TFE, HFP, and VDF, and optionally a
perfluorovinyl ether are blended with a perfluoropolymer.
[0024] Among the useful combinations are ratios of about 99.9
weight percent (wt %) to about 0.1 wt % of FEP with the balance
being THV, about 99.9 weight percent (wt %) to about 0.1 wt % of
ETFE with the balance being a copolymer derived from
tetrafluoroethylene-hexafluoropropylene-et- hylene (HTE).
[0025] The first layer of an article according to the present
invention includes one or more thermoplastic perhalogenated
polymers. These polymers typically have melting temperatures
ranging from about 100 to about 330.degree. C., more preferably
from about 150 to about 310.degree. C. Materials in this class
include FEP, PFA, and polychlorotrifluoroethyl- ene (PCTFE). FEP
resins are random copolymers of TFE with HFP. The HFP content in
FEP ranges from about 10 to 15 wt % in many commercial versions,
while others include HFP at levels of 25 wt % and 50 wt %.
[0026] The partially fluorinated-thermoplastics useful in the
invention include various combinations of interpolymerized units of
TFE, HFP, VDF, perfluoro alkyl or alkoxy vinyl ethers, and
nonfluorinated olefins. Materials in this class include TFE/HFP/VDF
copolymers such as THV, ETFE, HTE, polyvinylidene fluoride (PVDF),
TFE/P, polyethylenechlorotrifluoroet- hylene (ECTFE).
[0027] In one aspect, the invention comprises a "substantially
non-vinylidene fluoride containing" fluoropolymer, which means a
fluoropolymer lacking interpolymerized units of vinylidene
fluoride, such as PVF, ETFE, HTE, TFE/P, and
polychlorotrifluoroethylene (PCTFE).
[0028] A copolymer having a VDF content between about 3 and 30 wt %
(preferably between about 5 and 25) and a different copolymer
having a VDF content between about 20 and 60 wt % (preferably
between about 20 and 50) comprise a useful combination in the
present invention.
[0029] In one aspect, at least one layer comprises interpolymerized
units of a hydrogen-containing monomer having a pH at or below the
pH of vinylidene fluoride.
[0030] Partially fluorinated polymers of VDF, HFP and TFE are known
to be readily dehydro fluorinated by bases in the presence of a
phase transfer catalyst. This is thought to occur because the
methylene groups of VDF are surrounded by fluorocarbons (resulting
from an interpolymerized vinylidene fluoride monomer), which are
known to be electron-withdrawing groups. As a result, the hydrogen
of the methylene units become more acidic and are susceptible to
base attack to undergo dehydrofluorination. The newly formed C--C
double bonds enable bonding to organic and inorganic substrates
having nucleophilic functionalities. Monomers useful in polymers of
the invention which are similar to VDF in this respect include
CFH.dbd.CF.sub.2, CH.sub.2.dbd.CHF, CH.sub.2.dbd.CHR.sub.f,
perfluoroaryl vinyl ether, CF2.dbd.CHR.sub.f, wherein R.sub.f is a
C.sub.1-C.sub.10 perfluoroalkyl group.
[0031] Any known fluoroelastomer or perhalogenated elastomer can be
used when the material meets the definition required for the
inventive composition.
[0032] The perhalogenated polymer typically comprises
interpolymerized units of Formula I:
--CF(X)--CX.sub.2--, (I)
[0033] wherein each X is independently a halogen atom or
perhalogenated C.sub.1-C.sub.3 alkyl group. Useful examples include
interpolymerized units such as tetrafluoroethylene (TFE) and
chlorotrifluoroethylene (CTFE). Specific examples of suitable
monomers include TFE, perfluorobutylethylene, and HFP. In one
embodiment, at least one perhalogenated polymer comprises at least
40 weight percent (wt %) of its interpolymerized units of Formula
I. In another embodiment, at least one perhalogenated polymer
comprises at least 80 wt % of its interpolymerized units of Formula
I. In another embodiment, at least one perhalogenated polymer
comprises at least 95 wt % of its interpolymerized units of Formula
I. The perhalogenated polymer may further include interpolymerized
units derived from other perfluorinated monomers in various
combinations. These include homopolymers as well as copolymers
which have two or more different interpolymerized units of Formula
I.
[0034] The perhalogenated polymer also may comprise
interpolymerized units of Formula II: 1
[0035] wherein each Y is independently O or CF.sub.2; each Z is
independently F or R.sub.f wherein each R.sub.f is independently a
C.sub.1-C.sub.10 perfluoroalkyl group; and n is 0-3.
[0036] The perhalogenated polymer also may comprise
interpolymerized units of Fonnula II, above. The perhalogenated
polymer also may comprise interpolymerized units of the formula
--CF.sub.2--CF(X')--, wherein each X' is independently Cl, Br,
R.sub.f, O(R.sub.fO).sub.aR.sub.f, wherein each R.sub.f is
independently a C.sub.1-C.sub.10 perfluoroalkyl group and a is
0-10. or a unit according to Formula II (as described above). The
perhalogenated polymer also may comprise interpolymerized units of
formula --CF.sub.2--O--Y--CF.sub.2--, wherein Y is a bond or
CF.sub.2.
[0037] The perhalogenated polymer also may comprise
interpolymerized units of a perfluorinated vinyl ether of Formula
IV:
CF.sub.2.dbd.CFO(R.sub.fO).sub.aR.sub.f (III)
[0038] wherein each R.sub.f is independently a linear or branched
C.sub.1-C.sub.6 perfluoroalkyl group; and a is 0 or an integer from
1 to 20.
[0039] Specific examples of suitable perfluorinated monomers
include hexafluoropropylene (HFP), 3-chloropentafluoropropene, and
perfluorinated vinyl ethers such as CF.sub.2.dbd.CFOCF.sub.3.
CF.sub.2.dbd.CFOCF.sub.2CF- .sub.2OCF.sub.3,
CF.sub.2.dbd.CFOCF.sub.2CF.sub.2CF.sub.2OCF.sub.3,
CF.sub.2.dbd.CFOCF.sub.2CF.sub.2CF.sub.3,
CF.sub.2.dbd.CFOCF.sub.2CF(CF.s- ub.3)OCF.sub.2CF.sub.2CF.sub.3,
and CF.sub.2.dbd.CFOCF.sub.2CF(CF.sub.3)OC-
F.sub.2CF(CF.sub.3)OCF.sub.2CF.sub.2CF.sub.3.
[0040] The fluoropolymers useful in the invention also may comprise
interpolymerized units of --CF(X')--CX'.sub.2--, wherein each X' is
independently hydrogen, a halogen atom, a C.sub.1-C.sub.10 alkyl
group, R', OR', or O(R'O).sub.aR', wherein each R' is independently
a C.sub.1-C.sub.10 alkyl group (more preferably C.sub.1-C.sub.4)
which may be fluorinated or perfluorinated (as described above) and
wherein a is 0 or an integer from 1 to 10.
[0041] Specific examples of suitable partially fluorinated monomers
include vinyl fluoride and VDF, TFE, perfluorobutylethylene, and
HFP.
[0042] The fluoropolymers useful in the invention also may comprise
interpolymerized units of TFE and a non-fluorinated monomer having
interpolymerized units according to Formula V:
--CR.sub.2--CR.sub.2-- (IV)
[0043] wherein each R is independently hydrogen, a halogen atom, or
a C.sub.1-C.sub.8 alkyl group.
[0044] Specific examples of suitable monomers in this category
include nonfluorinated olefins such as ethylene and propylene.
[0045] In another aspect, the invention provides an article
comprising a first layer comprising a. blend as described above in
this section and a second layer bonded to the first layer. The
second layer may comprise a reinforcing material. Such a material
optionally may be used as a separate layer or included within a
layer in a multi-layer embodiment of the present invention. Such
reinforcing layers may include, e.g., wire or fiberglass braiding.
The second layer may comprise a polymer. Such polymers include
polyamides, polyimides, polyurethanes, polyolefins, polystyrenes,
polyesters, polycarbonates, polyketones, polyureas, polyacrylates,
polymethacrylates, acrylonitrile butadiene, butadiene rubber,
chlorinated and chloro-sulfonated polyethylene, chloroprene, EPM,
EPDM, PE-EPDM, PP-EPDM, EVOH, epichlorihydrin, isobutylene
isoprene, isoprene, polysulfides, silicones, NBR/PVC, styrene
butadienes, and vinyl acetate ethylenes, and combinations thereof.
The second layer may comprise an inorganic substrate such as metal,
glass, ceramic, and combinations thereof.
[0046] In another aspect, the invention provides an article
comprising a first layer comprising a blend of a partially
fluorinated-thermoplastic and a perfluorothermoplastic, and a
second layer bonded to the first layer, the second layer comprising
a polymer selected from elastomers, polyolefins, and polyamides
lacking pendant amines. In this embodiment, any known elastomer can
be used provided that the elastomer does not include a pendant
primary or secondary amine. Materials useful in this aspect include
polyamines, and polyolefins such as those polyolefins modified with
groups such as maleic anhydride, vinyl acetate, or carboxylic
acid.
[0047] In another aspect, the invention provides an article
comprising a blend of two or more fluoropolymers, which may be
perfluorinated, and a second layer bonded to the first layer, the
second layer comprising a partially-fluorinated thermoplastic
polymer, a perfluorinated thermoplastic polymer, or a combination
thereof. These fluoropolymers include those described above,
including such materials as chlorotrifluoroethylene.
[0048] One layer of an article of the invention can comprise one or
more partially-fluorinated thermoplastic polymer(s), and optionally
one or more perhalogenated polymer(s). Any of the polymers are
described above in this section meeting these general categories
can be used.
[0049] The article of the invention may also include a bonding
interface between the first layer and the second layer of the
invention. This interface consists essentially of a first material
having the composition of the first layer and a second material
having the composition of the second layer.
[0050] The blends of the invention, or a layer in a multilayer
article of the invention may include known adjuvants such as
antioxidants, conductive materials, carbon black, graphite,
fillers, lubricants, pigments, plasticizers, processing aids,
stabilizers, and the like including combinations of such materials.
In some embodiments involving a bonding interface consisting
essentially of the composition of the first and second layers of an
article of the invention, these adjuvants do not materially improve
the bonding properties between these two layers. This embodiment
excludes etching, corona discharge, adhesion promoter, or other
surface treatment that adds one or more chemical species or removes
one or more fluorine or other atoms or otherwise modifies the
composition of either layer is used in the bonding interface
between the first layer and the second layer of the invention.
Similarly, the first and second layers of the article of this
embodiment of the invention do not include various other elements
known to improve adhesion between a fluoropolymer and another
material, such as a tie layer and/or adhesive.
[0051] The absence of a surface treatment intended to improve
bonding can be noted by the critical surface tension or surface
energy of the layers in the invention. For example, one
fluoropolymer layer of one embodiment of the invention has a first
surface bonded to the second layer, wherein this first surface has
a surface energy below about 30 mJ/m.sup.2, below about 25, or even
below about 22 or 20 mJ/m.sup.2. Similarly, the partially
fluorinated layer of one embodiment of the invention has a surface
bonded to the first layer, wherein this bonding surface has a
surface energy below about 30 mJ/m.sup.2, below about 25, or even
below about 22 or 20 mJ/m.sup.2. In some embodiments, a difference
in surface energy between two layers is below about to 5
mJ/m.sup.2, or below about to 3 mJ/m.sup.2.
[0052] The present invention also comprises a blend of a polymer
having a surface energy below about 20 mJ/m.sup.2 and a polymer
having a surface energy having below about 25 mJ/m.sup.2, wherein
the difference of the surface energy between the first layer and
the second layer is from 1 mJ/m2 to 5 2 mJ/m.sup.2.
[0053] The blends of the invention comprising THV with FEP or other
polymers can provide lower surface energy than THV alone. These
embodiments are useful for example in anti-graffiti and/or
anti-soiling applications.
[0054] The bonding interface between the first and second layers
provides an interlayer adhesion level of at least about one Newton
per centimeter (N/cm), as measured by a peel test according to ASTM
D 1876. The interlayer adhesion of the present invention is
preferably at least about 2 N/cm, and more preferably at least
about 5 N/cm. In some embodiments of the present invention, the
interlayer adhesion above about 15 N/cm, above about 30 N/cm, or
even about 45 N/cm. Particular embodiments provide interlayer
adhesion above about 90 N/cm.
[0055] In another embodiment, the interlayer adhesion between the
first and second layers of the present invention is at least about
one Newton per centimeter (N/cm), as measured by the peel test of
ASTM D 1876. The interlayer adhesion of the present invention is
preferably at least about 2 N/cm, and more preferably at least
about 5 N/cm. In some embodiments of the present invention, the
interlayer adhesion above about 15 N/cm, or even about 30 N/cm.
[0056] In other embodiments of the invention, interlayer adhesion
between any two layers can be improved through any known means.
Such routes include, e.g., surface treatments, dehydrofluorinating
agents, tie layers, adhesives, and the like.
[0057] The thermoplastic polymer of one or more layer(s) of an
article of the invention, may include a conductive material to
provide an electrostatic dissipative (ESD) fluoroplastic
composition. In this aspect of the invention, the ESD polymer
composition comprises a sufficient amount of one or more layers to
provide ESD properties to the resultant article. Usually, up to
about 20 wt % of the conductive material is sufficient in one
layer, based on the total weight of that layer. In addition, a
minor amount, usually up to about 5 wt %, of another melt
processable thermoplastic material such as a hydrocarbon polymer is
used as a dispersing aid. In one embodiment of the invention, the
dispersing aid does not provide measurable improvement in bonding
between the first and second layers and can be used even when a
bonding interface between the first and second layers is required.
The ESD polymer composition preferably contains about 2 to about 10
wt % of the conductive material and about 0.1 to about 3 wt % of
the dispersing aid. Any known conductive filler may be used, such
as carbon black and/or graphite. Likewise, any known dispersing aid
may be used, such as any of a variety of hydrocarbon polymers. In
an aspect of the invention involving a multilayer hose such as for
conveying volatile fuel, the ESD composition is preferably included
in the interior layer of the hose that is in contact with the fuel.
The dispersing aid is preferably fluid at the processing
temperature of the layer in which it is used. Additionally, the
dispersing aid preferably is immiscible with the polymer of that
layer. Typical ESD additive compositions include the hydrocarbon
olefin polymers and the poly(oxyalkylene) polymers with the
conductive materials such as taught in U.S. Pat. No. 5,549,948,
which is herein incorporated by reference.
[0058] In another embodiment, the invention includes one or more
additional layer(s). In one aspect, this involves a third layer
comprising a polymer, the third layer being bonded to the second
layer on a surface opposite that to which the first layer is
bonded. A third layer comprising a polymer may be bonded to the
first layer on a surface opposite that to which the second layer is
bonded. In addition, a fourth layer comprising a polymer can be
bonded to an exposed surface of a multilayer article of the
invention. For example, when a third layer is bonded to the second
layer, a fourth layer can be bonded to the third layer or the first
layer. Other combinations will be apparent to those skilled in the
art and are included within the scope of this invention. The
composition of the one or more additional layer(s) may comprise any
polymer described above and optionally any known adjuvant.
[0059] In addition, other known polymers may be bonded to the
surfaces of the first and/or second layer that are not involved in
the bonding interface, as well as to third and/or fourth layers
such as described above. These other polymers include the
fluorinated and perfluorinated polymers described above as well as
non-fluorinated polymers such as polyamides, polyimides,
polyurethanes, polyolefins, polystyrenes, polyesters,
polycarbonates, polyketones, polyureas, polyacrylates,
polymethacrylates, acrylonitrile butadiene, butadiene rubber,
chlorinated and chloro-sulfonated polyethylene, chloroprene, EPM,
EPDM, PE-EPDM, PP-EPDM, EVOH, epichlorihydrin, isobutylene
isoprene, isoprene, polysulfides, silicones, NBR/PVC, styrene
butadienes, and vinyl acetate ethylenes, and combinations
thereof.
[0060] In another aspect, the invention provides a fuel hose
comprising a blend as described above. In another aspect the
invention provides a fuel hose comprising a multilayer article as
described above. For example, the invention provides a fuel hose
comprising a first layer which comprises a blend of two or more
fluoropolymers. This fuel hose further comprises a second layer
which comprises a fluoropolymer. In addition, an outer layer may be
bonded to either of the first or second layers. Also, an
intermediate layer comprising a partially-fluorinated polymer can
be bonded to the second layer, and optionally this intermediate
layer can be bonded to the intermediate layer. The inner layer can
comprise a partially-fluorinated elastomer.
[0061] Multi-layer articles prepared according to the invention can
be provided in a wide variety of shapes, including sheets, films,
containers, hoses, tubes, and the like. The articles are especially
useful wherever chemical resistance and/or barrier properties are
desired. Examples of specific uses for the articles include their
use in reflective materials, paint replacement films, drag
reduction films, fuel line and filler neck hoses, fuel tanks,
exhaust hoses, and the like. The articles are also useful in
chemical handling and processing applications, and as wire and
cable coatings.
[0062] The blends of the invention can be provided through any
known means. For example, twin screw compounding, batch mixing,
latex blending, dry blending.
[0063] One process for preparing a multi-layer article featuring a
fluoropolymer blend layer of the present invention involves
providing a first layer comprising a blend as described above,
providing a second layer bonded to the first layer, the second
layer comprising one or more polymer(s) as described above, and
heating at least one layer and the interface between the layers to
a temperature above the softening point or melting point of at
least one of the layers. Generally, the highest melting or
softening point of all components used in a blend of the invention
defines the preferred minimum temperature for preparing the
multi-layer article. For example, when a perfluorothermoplastic is
used in a blend, this layer is preferably heated to the melting
point of the perfluorothermoplastic or above, and when a
perfluoroelastomer is used in a blend layer, this layer is
preferably heated to the softening point or the melt processing
range of the perfluoroelastomer or above. In addition, the layers
are preferably pressed together, such as through a nip or platen or
other known means. Generally, increasing the time, temperature,
and/or pressure can improve interlayer adhesion. The conditions for
bonding any two layers can be optimized through routine
experimentation.
[0064] Another process for preparing a multi-layer article
featuring a fluoropolymer blend layer of the present invention
involves coextruding two or more layers through a die to form an
article. Such coextrusion processes are useful, e.g., for preparing
sheets, tubing, containers, etc.
[0065] Still another process for preparing a multi-layer article
featuring a fluoropolymer blend layer of the present invention
involves extruding one layer through a die to form a length of
tubing.
[0066] A second extruder supplies a crosshead die to coat another
layer of molten fluoropolymer onto a surface of the tubing. The
blend of the invention can be provided in either the inner or outer
layer, or both. Additional layers can be added through similar
means. Following the extrusion operations, the multi-layer article
may be cooled, e.g., by immersion in a cooling bath. This process
can be used to form multilayer sheets of the invention, as well as
other shapes, by using extrusion die shapes known in the art. The
blend of the invention can be provided to the extrusion process
through any known means. For example, dry input materials can be
blended before being supplied to an extruder, or a twin screw
extruder may be used to blend materials during melt processing.
[0067] Objects and advantages of this invention are further
illustrated by the following examples, but the particular materials
and amounts thereof recited in these examples, as well as other
conditions and details, should not be construed to unduly limit
this invention.
EXAMPLES
[0068] Materials
[0069] FEP, a TFE/HFP copolymer, available as Dyneon.TM. FEP 6307
from Dyneon LLC, Oakdale Minn.
[0070] PFA-Flex, a copolymer of TFE/HFP/PPVE, available as PFA-Flex
8515UHP from Dyneon
[0071] HTE-1500 a copolymer of TFE/HFP/ethylene, available from
Dyneon
[0072] PF-1, a copolymer of 76.0 TFE, 12.0 HFP, and 12.0 VDF (wt
%), Tm 237.degree. C., MFI 8.6 (all MFI data was measured using a
temperature of 265.degree. C. and 5 kg weight)
[0073] PF-2, a copolymer of a copolymer of 73.0 TFE, 11.5 HFP, 11.5
VDF, and 4.0 PPVE (wt %), Tm 222.degree. C., MFI 4.8
[0074] PF-3, a copolymer of 60.0 TFE, 18.0 HFP, and 22.0 VDF (wt
%), Tm 165.degree. C.
[0075] PF-4, a copolymer of 42.0 TFE, 20.0 HFP, and 38.0 VDF (wt
%), Tm 125.degree. C.
[0076] PF-5, a blend of three copolymers, each having a composition
of 73.0 TFE, 11.5 HFP, 11.5 VDF, and 4.0 PPVE (wt %), in a ratio of
8 wt % MFI 0, and 92 wt % of a 2:1 ratio of MFI 10 and MFI 400, Tm
230.degree. C., having a net MFI of 15, for greater detail, see WO
02/00741 or the procedures described in U.S. Pat. No.
6,242,548.
[0077] ETFE-EP-610, a copolymer of TFE/ethylene, available from
Daikin
[0078] FC-2145. a copolymer of HFP and VDF available from
Dyneon
[0079] Solef.TM. PVDF 1010, a homopolymer of VDF, available from
Solvay,. Paris, France
[0080] Solef.TM. HV 11010, a copolymer of HFP and VDF available
from Solvay
[0081] Test Methods
[0082] Permeation Constant:
[0083] Permeation constants were obtained using the procedure
described in ASTM D 814-86. (Reapproved 1991) with the following
changes and details. The glass jar of ASTM D 814 was replaced with
a Thwing-Albert Vapometer Permeability Cup as described in ASTM E
96-95. The fluoropolymer side of the test specimen was oriented
toward the test liquid. FE-5840Q elastomer (Shore A hardness of
about 60, available from Dyneon LLC, Oakdale Minn.) was used for
the gaskets instead of neoprene rubber and were located on both the
top and bottom of the test specimen. A circular disk of mesh screen
was used on top of the gasket to prevent the test specimen from
deforming during the test. The test liquid was 100 mL of CE 10 fuel
(10% ethanol, 45% iso-octane; 45% toluene). The test temperature
was 60.degree. C. The permeation constant (g.mm/m.sup.2 day) was
calculated by measuring the weight loss for a 30-day period using
Mettler AT 400 at an accuracy of 0.1 mg. A slope of the line
obtained by the least squares fit of weight loss (grams) versus
time (days) was divided by the area of the test specimen and
multiplied by its thickness to yield the permeation constant.
[0084] Contact Angles and Surface Tension:
[0085] Contact angles were measured using a VCA-2500XE (available
from AST Products, Billerica, Mass.). Ionized water and
n-hexadecane were used for contact angle measurements on the
fluoropolymer films described below. An average of measurements
made on 3 to 6 different drops of water or hexadecane was used for
the contact angle. Surface tension or surface energy of a solid
(.gamma..sub.s) was calculated using the following equations given
by Owens and Wendt (D. K. Owens and R. C. Wendt, J. Appl. Polym.
Sci. 13, 1741 (1969)) using the polar component of surface energy
(.gamma..sub.s.sup.P) and the dispersion component of surface
energy (.gamma..sub.s.sup.d).
(1+cos .theta.).gamma..sub.L1.sup.d=2{square root}{square root over
(.gamma..sub.L1.sup.d)}.times.{square root}{square root over
(.gamma..sub.S.sup.d)}+2{square root}{square root over
(.gamma..sub.L1.sup.P)}.times.{square root}{square root over
(.gamma..sub.S.sup.P)} Equation 1
(1+cos .theta.).gamma..sub.L2.sup.d=2{square root}{square root over
(.gamma..sub.L2.sup.d)}.times.{square root}{square root over
(.gamma..sub.S.sup.d)}+2{square root}{square root over
(.gamma..sub.L2.sup.P)}.times.{square root}{square root over
(.gamma..sub.S.sup.P)} Equation 2
[0086] wherein .theta. is the contact angle, .gamma..sub.L is
liquid surface tension, .gamma..sub.S is the solid surface tension
and the subscripts 1 and 2 refer to water and n-hexadecane,
respectively. The addition of d and p in the superscripts refers to
the dispersion and polar components of each. The known
.gamma..sub.L.sup.d and .gamma..sub.L.sup.P of each testing liquid
at 20.degree. C., i.e., water .gamma..sub.L.sup.d=18.7 and
.gamma..sub.L.sup.P=53.6 and for n-hexadecane
.gamma..sub.L.sup.d=27.0 and .gamma..sub.L.sup.P=0, were used for
the calculations. When the contact angles were measured, Equation 1
and 2 were solved simultaneously to give .gamma..sub.S.sup.d and
.gamma..sub.S.sup.P of the solid. The surface tension
(.gamma..sub.S) was defined as the sum of the .gamma..sub.S.sup.d
and .gamma..sub.S.sup.P of the solid. Reported values were the
average of the surface tension calculated from the contact
angles.
[0087] Thermal Lamination:
[0088] To facilitate testing of the adhesion between the layers via
a T-peel test, a strip of a sheet of 0.05 mm thick polyimide film
(available as Apical from Kaneka High-Tech Materials, Inc.,
Pasadena Tex.) was inserted about 0.25 in. (6.4 mm) along one short
edge between the two films described below before hot pressing. In
earlier samples a PTFE-coated fiber sheet was used, but it adhered
to the inventive films.
[0089] In some cases, a slight force was necessary to keep good
surface contact between the films. The polyimide sheet peeled away
from each material and was used only to create tabs of the
resulting laminate. These tabs were inserted into the jaws of a
test device in the peel test described later. The two-layer sheet
was heated under pressure at 290.degree. C. for 1-3 minutes between
the platens of a Wabash Hydraulic press to bond the layers, then
immediately transferred to a cold press. After cooling to room
temperature by a "cold pressing", the resulting sample was
subjected to T-peel measurement. The results are shown in the
tables below.
[0090] Peel Adhesion:
[0091] Peel strength between the layers was measured in accordance
with ASTM D 1876 (T-Peel Test). Samples were cut into strips 25.4
mm wide by about 2 to 2.5 in. (5 to 6.3 cm) long.
[0092] A Model 1125 tester (available from Instron Corp., Canton
Mass.) at 100 mm/min crosshead speed was used as the test device.
As the layers were separated, the average peel strength of the
middle 80% of the sample was measured. The values from the first
10% and the last 10% distance of the crosshead were omitted. When
the samples broke within the material without separating the layers
at the bonding interface, the peak value was used instead of the
average number. The values reported in the tables below were
averages of three tested samples.
EXAMPLES 1-21
[0093] In Example 1, a polymer blend composition of 95 weight
percent (wt %) FEP, and 5 wt % PF-1 was compounded in a
Plasticorder (an internal bowl mixer equipped with roller blades,
available from C.W. Brabender Instuments,Inc., South Hackensack,
N.J.) at 290.degree. C. for 20-30 min. at a mixing rate of 90-100
revolutions per minute (rpm). After mixing, the blend was collected
and formed into film having a thickness of 0.3 mm by pressing
between heated metal platens at 290.degree. C. in a Wabash
Hydraulic Press at approximately 30 Kpa pressure for approximately
1 min. The resulting film was visually clear. Samples were cut
1".times.2" peel testing. Examples 2-20 were prepared in
substantially as described in Example 1 except that the compounding
materials and ratios were varied as shown in the table below. In
addition, Examples 12 and 13 used a compounding temperature of
310.degree. C. rather than 290.degree. C.
EXAMPLES 22-28
[0094] Laminations of two layers were prepared as described above
in the Thermal Lamination section, and the materials varied as
shown in Table 2, below. Examples 22-27 and 29-37 were heat-pressed
for 2 min., Example 28 was heat-pressed for 1 min., and Examples
38-48 were heat-pressed for 3 min.
COMPARATIVE EXAMPLES C1-C3
[0095] Laminations of two layers were prepared as described above
in the Thermal Lamination section and were heat-pressed for 3 min.,
using FEP as the base layer and the material of the second layer
was varied as shown in Table 2, below.
1TABLE 1 Film Compositions Example Polymer A Wt % Polymer B Wt % 1
FEP 95 PF-1 5 2 FEP 90 PF-1 10 3 FEP 80 PF-1 20 4 FEP 70 PF-1 30 5
FEP 50 PF-1 50 6 FEP 10 PF-1 90 7 FEP 30 PF-1 70 8 FEP 80 PF-2 20 9
FEP 90 PF-2 10 10 PFA-Flex 90 PF-2 10 11 PFA-Flex 80 PF-2 20 12
ETFE-EP-610 80 HTE-1500 20 13 ETFE-EP-610 50 HTE-1500 50 14 PF-3 50
HTE-1500 50 15 PF-3 60 HTE-1500 40 16 PF-3 80 HTE-1500 20 17 PF-3
40 HTE-1500 60 18 PF-3 70 HTE-1500 30 19 PF-3 50 ETFE-EP-610 50 20
PF-3 30 PF-1 70 21 PF-1 50 HTE-1500 50
[0096]
2TABLE 2 Lamination of Blends Blend Layer Peel Example Example
Substrate Peel (lb/in) (N/cm) 22 1 PF-1 11.0 19.4 23 1 PF-3 7.0
12.3 24 2 PF-1 8.9 15.7 25 2 PF-3 6.1 10.7 26 3 PF-1 8.7 15.3 28 3
PF-4 8.2 14.4 29 4 PF-1 13.0 22.9 30 4 PF-3 11.0 19.4 tore 31 5
PF-1 16.0 28.2 tore 32 5 PF-3 7.9 13.9 33 7 PF-1 14.0 24.6 tore 35
6 PF-1 >12.0 >21.1 tore 36 6 PF-3 >12.0 >21.1 38 10
PF-2 8.0 14.1 39 10 PF-3 10.0 17.6 40 10 PF-1 3.6 6.3 41 11 PF-2
11.0 19.4 42 11 PF-3 >12.4 >21.8 pull out 43 11 PF-1 >7
>12.3 tore 44 10 PF-2 6.5 11.4 45 10 PF-3 4.5 7.9 46 10 PF-2 7.0
12.3 47 10 PF-1 8.5 15.0 tore 48 10 PF-3 14.0 24.6
[0097]
3TABLE 2A Comparative Peel Data Example Fluoropolymer Substrate
Peel (lb/in) Peel (N/cm) C1 FEP PF-2 5.0 8.8 C2 FEP PF-1 2.7 4.8 C3
FEP PF-3 <0.1 0.2
[0098]
4TABLE 3 Blend Laminations Blend Layer Example Example Substrate
Peel (lb/in) Peel (N/cm) 49 21 HTE-1500 >15.0 >26.4 50 21
PF-1 >14.0 >24.6 51 14 HTE-1500 >15 >26.4 tore 52 14
PF-1 >14 >24.6 tore 53 18 HTE-1500 >15 >26.4 tore 54 18
PF-3 >14.0 >24.6 55 16 HTE-1500 >20 >35.2 tore 56 16
PF-1 13.7 24.1 57 17 HTE-1500 >20 >35.2 tore 58 17 PF-1 14.6
25.7 59 12 ETFE-EP-610 >10 >17.6 60 20 FEP 4.0 7.0
EXAMPLES 61-68
[0099] In Example 61, a polymer blend composition of 80 wt % PF-1,
and 20 wt % PF-4 was compounded and pressed into a film as
described in Example 1. Examples 62-68 were prepared in
substantially the same way as described in Example 61 except that
the compounding materials and shown in Table 4, below. Also,
Examples 61-68 were heat-pressed for 1 min. at 290.degree. C. to
prepare the films, while Example 64 was heat-pressed for 1 min. at
310.degree. C. The resulting films were visually clear. Samples
were cut and tested as described in the Peel Adhesion section.
EXAMPLE 69
[0100] This was prepared as in Example 1 except that a polymer
blend composition of 80 wt % FEP, 15 wt % PF-1, and 5 wt % of
FC-2145 was used.
EXAMPLE 70
[0101] A polymer blend composition was prepared substantially as
described in Example 1 except that the compounding mixture was 20
wt % FEP 80 wt % Solvay-PVDF. After mixing, the blend was collected
and formed into a film and samples were cut as in Example 1.
EXAMPLES 71-90
[0102] Laminations of two layers were prepared as described above
in the Thermal Lamination section, and the materials were varied as
shown in Table 4, below.
COMPARATIVE EXAMPLE C4
[0103] Laminations of two layers were prepared as described above
in the Thermal Lamination section and were heat-pressed for 3 min.,
using FEP as the base layer and PF-2 as the second layer.
5TABLE 4 Blend Compositions Polymer Polymer Polymer Example A Wt %
B Wt % C Wt % 61 PF-2 80 PF-4 20 62 PF-2 80 PF-3 20 63 PF-2 50 PF-4
50 64 FEP 80 PF-2 10 PFA 10 65 FEP 80 PF-2 10 PF-3 10 66 FEP 80
PF-2 10 PF-4 10 67 FEP 90 PF-2 5 PF-3 5 68 FEP 90 PFA 10 69 FEP 80
PF-2 15 FC-2145 5 70 FEP 20 HV 80
[0104]
6TABLE 5 Blend Laminations Blend Layer Peel Peel Example Example
Substrate (lb/in) (N/cm) 71 61 FEP 12.0 21.1 72 62 FEP 9.0 15.8 73
63 FEP 16.7 29.4 74 63 Example 64 18.0 31.7 75 64 PF-3 12.0 21.1 76
64 PF-4 11.0 19.4 77 61 PFA 10.0 17.6 78 61 Example 68 10.0 17.6 79
65 PF-3 18.0 31.7 80 66 PF-3 16.0 28.2 81 65 PF-2 8.0 14.1 82 67
PF-3 8.9 15.7 83 68 PF-2 4.0 7.0 84 68 PF-3 0.4 0.7 85 68 PF-4 0.3
0.5 86 69 PF-2 9.2 16.2 87 69 PF-3 23.5 41.4 88 69 PF-4 12.9 22.7
89 70 HV >25.0 >44.0 C4 -- PF-2 3.5 6.2
EXAMPLES 90-104
[0105] Various weight ratios of a perfluorothermoplastic (FEP) were
tumble blended with a partially-fluorinated polymer (PF-3), and
then films were extruded using a temperature between 300 and
360.degree. C. A disc having a diameter of 7.72 cm was cut from
each film sample and used for permeation testing. Results are
summarized in Table 6, below.
[0106] In the table below, "n/m" indicates that a property was not
measured.
COMPARATIVE EXAMPLES C5-C9
[0107] Homopolymer films were extruded, cut, and tested as in
Example 93. Results are summarized in Table 6, below.
[0108] Various modifications and alterations of this invention will
become apparent to those skilled in the art without departing from
the scope and principles of this invention, and it should be
understood that this invention is not to be unduly limited to the
illustrative embodiments set forth hereinabove. All publications
and patents are herein incorporated by reference to the same extent
as if each individual publication or patent was specifically and
individually indicated to be incorporated by reference.
7TABLE 6 Permeation and Surface Energy Polymer blend Permeation
Surface ratio (wt %) Constant energy Example FEP (g .multidot.
mm/m.sup.2 .multidot. day) (mJ/m.sup.2) PF-3 90 90 10 0.78 18.9 91
80 20 1.06 18.9 92 70 30 n/m 20.0 93 50 50 2.21 20.3 C5 100 0 0.59
17.6 C6 0 100 9.5 21.7 PF-1 94 90 10 0.71 n/m 95 80 20 0.86 n/m 96
50 50 1.00 19.4 C7 0 100 2.44 n/m PF-5 97 90 10 0.65 n/m 98 80 30
0.82 n/m 99 50 50 1.23 18.6 C8 0 100 3.12 n/m PF-2 100 90 10 0.70
n/m 101 50 50 1.19 18.5 C9 0 100 3.63 n/m
* * * * *