Note: Descriptions are shown in the official language in which they were submitted.
-` -1- 2~236 '''
HOT PLASTISOL COMPOSITIONS
Backaround of the Invention
This invention relates to plastisol
compositions. More particularly the invention relates to
thermally stable plastisol compositions which are capable
of being hot applied to metal surfaces for adhesive and
sealant purposes.
Adhesive and sealant compositions are widely used
in many commercial and industrial production processes. A
multitude of such compositions have been developed over
the years, many of which were designed for a special use.
Adhesive compositions generally are used to bind two
substrates together. Sealant compositions generally are
used to form a load-bearing elastic joint between two
substrates. The sealants also exclude dirt, moisture and
other materials from the joint and form a smooth juncture
at the joint. Necessarily, there is~some overlap in the
functions of the adhesive and sealant compositions.
The automotive industry is a major user of both ~-
adhesive and sealant compo~sitions. Automobiles are
assembled from several structural components. ~The
components are joined together in various fashlons
depending on the particular components and the degree of
stress that will have to be endured. For certain assembly
steps an adhesive composition applied as a liquid and
~ subsequently hardened provides sufficlent bonding
strength. For example, metal assemblies of door panels,
quarter panels, tailgates, and roofs use adhesive
compo~sitions. These same assemblies also use sealant ~-
compositions at a~late~r stage in the assembly line. Still
30~ ~other~automobile assemblies which are~welded or bolted
together~use sealant compositions in their seams. The
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201(~23~
wheel house, shock tower, rocker panel, firewall, floor
hem flange, floorpan, and trunk are a few examples of
where sealants, but not adhesives, are used.
Typical automobile body assembly lines contain a
separate body shop and paint shop areas where adhesives
and sealants are individually used in each area
respectively. Adhesive compositions applied in the body
shop area are normally high strength epoxy or
modified-epoxy adhesives which are capable of bonding to
oily galvanized steel. In some cases vinyl plastisols are
employed, however, these applications are normally limited
to situations that do not require high bonding
performance. In any case, these materials are applied at
room temperature and later cured through exposure to
heat. A current weakness of these materials is that in
order to apply them, they must be of low enough viscosity
to be mechanically pumped with adequate flow rates.
Normally, because of their low viscosity these materials
are easily displaced when exposed to liquid impingement by
various cleaning solutions (washes) to which the assembly
body parts are exposed.
Recently a new class of materials referred to as
curing hot applied adhesives have been introduced in the
automotive body shop. These are urethane or
epoxy-modified urethanes and are solid or semi-solid at
room temperature. These adhesives function by changing
from a flowable fluid at an elevated application
temperature to a bonding solid at use temperature. The
hot applied adhesives have a number of characteristics -
30 which make them attractive for use in the body shop area. -
They are usually solvent free and thus no special fume
- collection hoods are needed. They have low viscosities
when made fluid and thus flow readily to fill gaps and wet
the substrates to be bonded. Most importantly the resins
~- ~' - '
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after application provide a high strength bond and cure to
an even higher strength after passage through drying ovens
at a later stage on the line. Additionally, the applied
adhesive compositions have a rapid set time. They will
not be displaced when exposed to liquid impingement by
various washes and electrophoretic priming fluids to which
the assembled body parts are subjected.
The assemblied parts as they move from the body
shop area are subjected to sealing, painting, and final
oven curing in the paint shop area. Sealant compositions
used in this area must also have a certain set of
characteristics to be acceptable. Vinyl plastisol
compositions have been found to have those needed
characteristics. Basically, a vinyl plastisol is a finely
divided polyvinyl chloride resin suspended in a
plasticizer. The plastisols are liquids which are applied -
at room temperature to the substrate. The liquid is
converted to a solid through exposure to heat. In effect,
the heat causes the suspended resin particles to be fused
or dissolved in the plasticizer. A solid product results
upon subsequent cooling.
Vinyl plastisols are excellent as sealants in the
paint shop area of the body assembly line. They flow
readily at room temperature to fill seams and body joints
which need to be sealed. They adhere well to primed metal
surfaces. They can be painted over without leaching or
causing other cosmetic problems. Finally, they are
durable enough to withstand normal weather and user
exposure. Another important quality of the vinyl
plastisols is that they are not expensive. The plastisols
would ideally be used in all adhesive and sealing phases
of the automotive assembly process if they had better
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_4- 2Q~6
metal bonding properties and could withstand the washes
and primer applications experienced in the body shop area
of the process.
Accordingly, a need exists for a product with
both strong adhesive and excellent sealant properties and
for compositions which combine the characteristics of both
the curing hot applied adhesives and the vinyl plastisols. -
Summary of the Invention
That need is met by the present invention which
provides a thermally stable hot applied plastisol
composition. That composition has a host of qualities :
which makes it attractive for bonding and/or sealing - -
joints areas in metal assemblies such as automobile bodies
and parts thereof.
The hot applied thermally stable plastisol -
composition of the present invention comprises as a
principal component thereof from about 20~ to about 35% of -
a finely divided polyvinyl chloride resin. The
composition preferably contains a mixture of two polyvinyl
chloride resins which comprise about 23-32% and most
preferably about 25-30% of the composition. The first
resin may be a homopolymer dispersion resin with inherent
viscosity of about 1.00 ml/g and is preferably between 50
and 100% and most preferably between 50% and 75~ of the
resin system. The second resin is a blending resin that
may be a copolymer of vinyl chloride and maleic ester with
inherent viscosity of about .97 ml/g and is preferably
between 0 and 50% and most preferably between 25% and 50% ~
of the resin system. ~ -
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_5_ 2Q~3~
A second major component of the present
composition is from about 15% to about 35% of a
plasticizer. The plasticizer is preferably diisodecyl
phthalate and preferably is about 19-30% and most
preferably about 22-30% of the composition.
Also included is about 2-25% of a thermoplastic
polymeric resin, preferably about 5-20% and most
preferably about 10-15% of a vinyl acetate/ethylene
copolymer having a vinyl acetate content preferably of
about 50-70% and most preferably about 60-65%.
Finally there is present about 3-15% of an
adhesion promotion system. The adhesion promotion system
preferably comprises about 5-13~ and most preferably about
5-11% of the total composition. The adhesion promotion ~ ;
system preferably contains an unsaturated organosilane
(between about 0.1 and 1%), an acrylic monomer (between 2
and 8%), an unsaturated acid or anhydride monomer (between -
0.1 and 2%) an epoxy or modified epoxy resin (between 0.5
and 4%) and a hardening agent for the eposy resin, such as
a polyamide (between 1 and 5%).
Optionally the composition also contains filler,
waxes, heat stabilizers, pigment, wetting agents and
various combinations and mixtures thereof.
The composition of the present invention has
both adhesive and sealant characteristics which make it
especially useful in the assembly of metal automotive
parts. The plastisol composition of the present invention
is thermally stable, can be hot applied to automotive
parts for adhesive and sealant purposes, and can
subsequently withstand the successive steps of a primer
application, primer wash-off, top coat paint application
and oven bake.
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The preferred method of bonding and/or sealing
using the present composition involves hot applying the
plastisol composition to joint areas of a metal assembly,
followed by cooling the composition sufficiently to
achieve sufficient bonding. If an automobile body or a
part thereof is being sealed in this manner, the method
may in some instances further involve applying a primer
composition to the metal assembly, heating the metal
assembly to cure the primer, and applying additional
plastisol composition to joint areas to form a sealed
smooth surface. In any event, it will usually involve
applying a paint composition to the metal assembly, and
baking the metal assembly to cure the plastisol i -
composition and the paint composition.
Accordingly, it is an object of the present
invention to provide a hot applied thermally stable - -
plastisol composition having adhesive and sealant
qualities useful in the assembly of automobile bodies, and
to a method of bonding and/or sealing joint areas in metal
assemblies using such a composition. Other objects and
advantages of the invention will become apparent from the
following detailed description and the appended claims.
Detailed Descri~tion of the Invention
As mentioned the composition of the present
invention comprises as major ingredients finely divided
polyvinyl chloride resin, plasticizer, thermoplastic
polymeric resin and an adhesion promotion system. Each of
the individual components of the composition will be
discussed in detail as well as the composition's mode of
use. All percentages and ratios are by weight unless
otherwise stated.
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_7_ 2~ 3~,
Polyvinyl chloride resins used in the
compositions of this invention are finely divided resin -
particles which are capable of being dispersed in a
plasticizer. The resins are well known and have been
widely used in plastisol compositions. The polyvinyl
chloride resins include polymers of vinyl chloride as well
as copolymers of vinyl chloride with copolymerizable vinyl
addition monomers. Examples of such vinyl addition
monomers include vinyl acetate, the vinyl acetals, maleic
esters, styrene, vinylidene chloride and acrylonitrile.
The particularly preferred polyvinyl chloride resins are
the fine particle dispersion type homopolymer resins and
vinyl chloride/maleic ester copolymers in a monomer weight
ratio of vinyl chloride to maleic ester of from about 99:1
to about 90:10. Blends of several different polyvinyl
chloride resins may also be used and will also be referred
to as the polyvinyl chloride resin, even though more than
one resin may actually be present. Actually, as
mentioned, a blend of 50-100~ and most preferably 50-75%
of a homopolymer dispersion resin and 0-50% and most
preferably 25-50% of a vinyl chloride/maleic ester
copolymer blending resin is preferred.
Plasticizers useful in the present invention
include monomeric types selected to achieve desired
characteristics such as proper gelation, fusion, and flow
properties. Examples of such monomeric plasticizers
include monomeric esters of phthalic, benzoic, succinic,
adipic, sebacic, talic, lauric, azelaic, caprylic,
hexanoic, phosphoric, oleic, glutaric, trimellitic and
stearic acids. Specific plasticizers include dioctyl
phthalate, ethylene glycol dibenzoate, dioctyl succinate,
dibutyl sebacate; dibenzyl azelate; didecyl glutarate and ~ -
similar compounds. Other monomeric plasticizers include
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2~23~, :
--8--
esters of 2, 2, 4-trimethyl-1,3-pentanediol, citric acid
esters and n-ethyl toluenesulfonamide. Preferred is
diisodecyl phthalate.
Polymeric plasticizing agents can be used in
conjunction with the monomeric plasticizers in order to
achieve special characteristics such as permanence,
weathering resistance, and especially paintability.
Polymer plasticizers useful in the present invention
include the higher molecular weight polymeric acid esters
~molecular weights greater than 1000). Examples of these
polymeric plasticizers include esters of succinic, adipic,
sebacic, talic, lauric, azelaic, caprylic, hexanoic,
benzoic, phthalic, phosphoric, oleic, glutaric,
trimellitic, and stearic acids, including mixtures or
blends of these compounds. The polymeric plasticizers
have low diffusion rates because of their higher molecular ;
weights and also act to retard the migration of other
components from the applied compositions. Additionally,
low molecular weight chlorinated paraffinic oils and
epoxidized soybean oil can be used as a co-plasticizers.
Again, blends of several different plasticizers may be
used, but will be referred to simply as the plasticizer.
A third essential component of the compositions
is a thermoplastic polymeric resin which is capable of
softening at application temperatures sufficiently to be -
flowable. Resins of this nature are commonly referred to
as hot applied resins. The resins are characterized by
their ability to set to a solid material by cooling rather
than by solvent evaporation or chemical reaction. Thus,
the resins are reduced to a soft or molten state by
inc~easing temeprature. Most of these resins
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progressively soften over a wide temperature range, though
some may actually have very narrow melting ranges and
become a true liquid. Each type of resin is useful herein
and is referred to as a hot applied resin. Typical resins
are solid or semi-solid pastes at room temperature with
softening temperatures of about 200F to about 375F.
Examples of thermoplastic polymeric resins include the
polyethylenes, polyamides, polyvinyl butyrals, polyvinyl
acetates, cellulose derivatives, polyesters, polymethyl
methacrylates and ethacrylates, polyvinyl ethers and
polyurethanes. Specific examples of such thermoplastic
resins include ethylene ethyl acrylate copolymers, vinyl
acetate styrene butadiene block copolymers and butyl
rubber.
Preferred thermoplastic resins are those polymers
that show solubility and compatibility with polyvinyl
chloride polymers such as ethylene vinyl acetate, vinyl
acetate ethylene, vinyl acetate, acrylonitrile,
acrylonitrile butadiene copolymer, chlorinated ethylene
vinyl acetate, polyepsilon caprolactone, methyl
metacrylate and polybutylene terephthalate. An ethylene
vinyl acetate having a 20-80% vinyl acetate content is
preferred. Vinyl acetate ethylene copolymers having a
vinyl acetate content of preferably 50-70% and most
preferably 60-65% are highly preferred because of their ` -
balance of compatibility, flow, adhesion and flexibility.
~ he adhesion promotion system found in the
current compositions preferably contains an unsaturated
organosilane; an acrylic monomer; and an unsaturated acid
or anhydride monomer. Most preferably it also contains an
epoxy resin or modified epoxy resin and a hardening agent
2~
--1 0-- ' '
for the epoxy resin, such as a polyamide or modified
polyamide. All of the unsaturated materials are capable
of polymerization with peroxide initiation and heat. The
formation of a highly functionalized oligomeric or
polymeric modified acrylic species in situ (after heating)
in concert with the reacted epoxy resin presumably is what
is responsible for the tenacious bonding of the current
adhesive to oily metals.
Examples of unsaturated organosilanes are the
vinyl, acrylics and methacrylic types such as vinyl
trichlorosilane, vinyl triethoxy silane, vinyl trimethoxy
silane, vinyl-tris B-methoxy-ethoxy silane,
3-methacryloxypropyl trimethoxy silane, 3-methacryloxy
propyl-tris-2 (methoxy-ethoxy) silane and vinyl triacetoxy
silane. Examples of acrylic monomers are any of the free
radical induced polymerizable mono or multifunctional
acrylic or methacrylic monomers such as trimethalopropane
trimethacrylate, hexane diol diacrylate, and butyl
methacrylate. Examples of unsaturated acid or anhydride .
monomers are the vinyl, acrylic, and methacrylic mono or
poly functional acid or anhydride materials maleic,
acrylic, crotonic, methacrylic, oleic, linoleic, and
tetrahydrophthalic acid or anhydride.
Examples of unmodified epoxy resins are those
based on bisphenol-A and epichlorohydrin with typical
properties that includes an epoxy value of 152-155
equiv./lOOg and a weight per epoxide of 182-192. Other
typical epoxy resins are phenol novolac,
triphenylolmethane, and tetrabromo bis-A. An example of a
modified epoxy resin includes the preferred elastomeric
modified liquid epoxy resin which is a 40~ ~dduct of
carboxylated acrylonitrile butadiene elastomer and a
liquid bisphenol-A and epichlorohydrin type epoxy. That
adduct has a weight per epoxide of 325-375. Curing
~. . .
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for the epoxy or modified epoxy resin is accomplished by
reacting the resin with an appropriate curing or hardening
agent. Typical hardening agents a polyamides,
diethylenetriamine, methane diamine, m-phenylene diamine,
diaminodiphenyl sulfone, tris (dimethyl amino methyl)
phenol, dicyandiamide, BF3-monoethyl amine and nadicmethyl
anhydride. Preferred is a modified polyamide hardening
agent such as a latent polyamide dispersion which is an
adduct of phthalic anhydride and diethylenetriamine in an
unmodified liquid epoxy resin. The epoxy or modified
epoxy resin~hardening age~t system apparently modifies the
galvanized surface by reacting with and/or to the adhesion ~ :
promotion system in the preferred embodiment.
It has been found that inclusion of the adhesion
promotion system in the compositions at the stated level
significantly increases the adhesion of the composition to
a metal surface without adversely affecting the qualities
of the applied composition. That is, the composition's
resistance to primer wash, paintability, viscosity
stability etc. are not adversely affected by the adhesion
promoter. Other adhesion promoters are also preferably
used with the current materials and, again, reference to
the adhesion promoter is reference to the adhesion
promoter system unless otherwise indicated.
The compositions of the invention are formulated
with the above essential components to achieve a product
having the desired set of characteristics considering
their intended use. The composition is intended as an -
adhesive and sealant for use in the assembly of metal
automotive parts. As such the compositions are able to
flow at application temperature with the proper wet-out
onto a surface, i.e., they are "pumpable". Upon cooling
an initial degree of adhesion is attained as discussed
below. Additionally, because of the intended use, the set
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-12- 20~
composition is capable of receiving a primer wash without
experiencing wash-out. Finally, the composition is able
to accept a primer and top coat paint and also to
withstand multiple oven bakes. The composition also has a
final degree of adhesion which is very durable.
Optional components of the composition of the
invention comprise waxes, heat stabilizers, fillers, --
pigments, and wetting agents. Such components are readily
available. Amorphous waxes, carnauba wax, castor oil wax
and various synthetic waxes was useful. Examples of heat ;
stabilizers include lead and barium- cadmium-zinc
systems. Fillers include ground and precipitated calcium
carbonate, ground silica, clays and talcs. Examples of ;~
wetting agents are polyethylene glycol derivatives. -~
Compositions of the invention with the
immediately aforedescribed qualities comprise (a) from
about 20% to about 35% of the finely divided polyvin~l
chloride resin, (b) from about 15% to about 35% of the
plasticizer, (c) from about 2% to about 25% of the
thermoplastic po~ymeric resin, and (d) from about 3% to ~ -
about 15% of the adhesion promotion system. A preferred
composition consists essentially ~a) from about 23% to
about 32% of the polyvinyl chloride resin, (b) from about
lg% to about 30% of the plasticizer, (c) from about 5% to -
about 20% of the thermoplastic polymeric resin, (d) from
about 5% to about 13% of adhesion promoter, and (e) the
balance selected from the group consisting of a wax, heat
stabilizer, filler, pigment, wetting agent, and mixtures
thereof.
A particularly preferred composition in terms of
performance and cost considerations consists essentially ~ -
of (a) from about 25% to about 30% of the polyvinyl
chloride resin, (b) from about 22% to about 30% of a
plasticizer, (c) from about 10% to about 15% of the :
20~
-13-
thermoplastic polymeric resin, (d) from about 5% to about
11% of adhesion promoter, (e) from about 15% to about 20%
of a filler, (f) from about 0% to about 8% wax, and (g)
from about 1% to about 4% of a heat stabilizer
The aforedescribed compositions of the invention
are unique in their ability to act as a structural
adhesive and a sealant in the assembly of automotive
bodies. Thus, the compositions are used in the body area
of the assembly to bond various steel components such as
hoods and roof panels. Additionally, the compositions are
used in the body shop area where certain components which
demand greater structural bonds as obtained by welding
require a sealant to smooth over the weld. The
compositions are heated from about 90F to about 160F and
applied in any convenient manner, such as pumping,
troweling, flowing! brushing or spraying. The
compositions are thermally stable so that they can be
heated and drawn from by a pumping operation for prolonged
periods. Upon cooling the compositions harden to a state
with an initial degree of adhesion which is adequate for
the intended purpose. This solidification occurs depite
the plastisol nature of the compositions.
The assembled automotive body components or body
shell is next prepared for painting. Typically this
involves phosphate cleaning, washing, immersing the body
shell in a primer bath, applying an electric charge to
effect electrodeposition of the primer to the body shell,
and removing the primed body shell from the bath. The
compositions originally applied as adhesives and sealants
30~ rémain in tack. That is, they are not washed out onto
adioining surface areas of the body shell.
Subsequent to the priming step, if one is used,
and prior to an oven bake, the body shell is top coated
with a paint and oven baked to a totally cured state by
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plastisol fusion of the sealer and also the top coat
paint. The fusion temperature is well above the -
aforementioned application temperature. The applied
compositions of the invention are also able to withstand
these operations without causing cosmetic-type problems
such as discoloration, tackiness, cracking, etc. -
It should be apparent the compositions of the
invention enjoy all the qualities of previously used hot
applied adhesive compositions and vinyl plastisol
compositions, collectively. The synergistic nature of the
composition components without adverse properties is very
unexpected. An added benefit flowing from one composition
having such qualities is reduced inventory in not having
to stock two separate products as well as a consequent
15 reduced administrative burden. -
The following examples illustrate the invention.
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-15- 20102~ :
Example I
A preferred thermally stable hot applied
plastisol composition has the following formulation:
% , .
Polyvinyl chloride dispersion resin (1)
19 .00
Polyvinyl chloride blending resin (2)8.00
Diisodecyl phthalate plasticizer 28.00
Epoxidized soybean oil plasticizer (3) 2.00
10 Vinyl acetate ethylene copolymer thermoplastic
resin (4) 13.00
3-methacryloxypropyl trimethoxy silane adhesion
promoter (5) 0.30
Elastomeric modified liquid epoxy resin (6) 2.00
15 Calcium organic thixotropic agent (7) 0.50
Methacrylate ester adhesion promoter (8) 4.~0
Calcium carbonate filler (9) 8.04
Hydrophobic fumed silica filler (10)8.00
Calcium oxide filler 2.00
20 Anionic surfactant wetting agent (11) 0.16
Modified polyamide hardening agent (12) : 3.0
Cumene hydroperoxide 0.08
Tri-basic lead sulfate heat stabilizer (13) 1.00
Hydroquinone monomethyl ether 0.02
25 Tetrahydrophthalic anhydride adhesion promoter 0.30
Carbon black pigment 0.05
Titanium dioxide pigment 0.05
100 . 00
~13 A homopolymer available from Huls Corp. as Vestolit
- 7031
.
-16-
(2) A copolymer of vinyl chloride and dibutyl maleate
available from The Goodyear Tire and Rubber Co. as
Pliovic MC-85
(3) Available from the C.P. Hall Co. as PlastHall ESO
(4) A hot applied resin available from USI Chemicals Co.
as Vynathene EY80031
(5) Available from Dow Corning as Z-6030 Silane
(6) Available from Wilmington Chemical Corp. as Heloxy
8005.
(7) Available from Ashland Chemical Co. as Ircogel 903
(8) Available from Sartomer Co. as Chemlink 9010
(9) Available from H.M. Royal Inc. as Roy Cal L
(10) Available from Cabot Corp. as Cab-0-Sil TS-720
(11) Available from BYK Chemie USA as Byk-W 960
15 (12) Available from Ciba-Geigy Corp. as Hardener HY 940
(13) Available from Eagle Picher Co. as EPIstatic
.. ..
The above composition was subjected to various tests to
demonstrate its suitability for the intended use.
20 Initially the thermal stability of the composition at : -
application temperature is determined. Samples of the
current composition were held in an oven at 120F and
140F respectively and the viscosity of each tested over a
period of time. Viscosities of the samples, as expressed
in centipoises adjusted to 81.5F was as follows:
:'
Hrs 120F 140F
Initial 2,963,800 2,963,800
1 2,740,500 6,252,400
30 7 2,801,400 -
.
-17- ~ ~10~36
The above results show that the composition's
viscosity remains substantially constant at 120F for at
least seven hours. At 140F, however, the viscosity of
the composition increases significantly over time. Thus,
the composition is viscosity stable up to at least 120F.
Another set of tests was used to show that the
composition of this example has a sufficiently low
viscosity at a pre-gel temperature to be pumpable. The
viscosities of a sample of the composition is measured at
various temperatures and plotted. Readings from the plot
are as set forth below:
Tem~erature (F)ViscositY (centipoises~
1,640,240
lS 80 1,250,480
990,640
787,640
100 519,680
110 373,520
120 292,320
The above results show the viscosity of the ~-
composition decreases with temperature and is low enough
to be readily pumped at an application temperature of
25about 120F. The application temperature is lower than
the temperature at which gelation begins.
Example II
The formulation disclosed in Example I was tested
for adhesive strength on three galvanized steel substrates
under various exposure conditions. The numbers reported
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2ol~2~6
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are the force to detach 1" x 4" metal coupons with a 1
in.2 bonded area pulled at 2"/minute. The specimens
were heat cured for 20 minutes at 325F and had a bond
thickness of 0.030". An average fading force from three
replicates is reported. % CF refers to the % of cohesive
failure for a given condition.
', '. . ...
Adhesive Testing Results
1 0
. -
ELECTRO ---
Shear Overlaps HOT DIP GALVANEAL GALVANEAL -
Initial 389 100% CF 448 100% CF 463 100% CF
3 wks humidity 451 80% CF 477 67% CF 412 72% CF
3 wks 158F 654 100% CF 756 100% CF 659 93% CF
250 hrs. salt spray 441 53% CF 550 57% CF 369 47% CF -
Corrosion* 548 78% CF --- ---
*Exposed to 30 cycles each of: 5 hours at 158F, 15
minutes 5% sodium chloride solution; 19.25 hours
100F/100% humidity.
Exam~le III
.
This example demonstrates the need for an
adhesion promotion system in the composition. A set of
partial compositions (i.e. containing polyvinyl chloride
resin containing but without a thermoplastic polymeric
resin) were made and then tested for short term and long
term adhesion. The compositions are:
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-19- 201{~
Parts bv Wei~ht
Homopolymer dispersion
resin 20.0 20.0 20.020.0 20.0 20.0
Copolymer blending
resin 8.4 8.4 8.48.4 8.4 8.4
Calcium carbonate
filler 39.8 39.8 39.839.~ 39.8 39.8 -
DIDP plasticizer 20.0 20.3 24.720.3 23.2 20.1
t-butyl perbonzoate0.08 0.08 0.080.08 0.08 0.08
tribasic lead 1.1 1.1 1.1 1.1 1.1 1.1
10 trimethalopropane ~ .
trimethacrylate 4.7 - 4.7 4.7 4.7 4.7
methacrylate silane 0.3 0.3 - 0.3 0.3 0.3 :
tetrahydrophtahlic
anhydride 0.3 0.3 0.3 - 0.3 0.3
15 elastomeric modified
epoxy resin 2.1 2.1 2.1 2.1 2.1
modified polyamide 3.2 3.2 3.2 3.2 - 3.2 - .: .
Adhesion Initial 10 8.5 1 9.5 3.5 10
20 Adhesion 2 weeks at room :
temperature 10 4.0 1 10 1 4 :
Adhesion 4 weeks at room .; ~
temperature 10 9.0 2 10 1 10 -
Adhesion results were obtained as qualitative
pulling of 1/2" x 1/2" bends of adhesive baked on a hot
dipped galvanized panel for 6 minutes at 350F. A rating
of 10 was judged as best with 100% cohesive failure and a
rating of 0 was judged as worst with total adhesive
: 3Q failure coupled with little or no failing force. Separate
adhesions were pulled for samples made fresh and then aged
at room temperature for two and four weeks respectively.
:
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,,
Exam~le IV :
The composition in Example I can be modified to
improve the paintability of the formulation. The :'
composition of a paintable material is as follows:
%
Polyvinyl chloride dispersion resin 19.00
Polyvinyl chloride blending resin 8.00
Diisodecyl phthalate plasticizer 8.00
Vinyl acetate ethylene copolymer
th0rmoplastic resin 13.00 :.
3-methacryloxypropyl trimethoxy silane ;:
adhesion promoter 0.30 ~ :
Elastomeric modified liquid epoxy resin 2.00 ~ :
Methacrylate ester adhesion promoter4.50 ~ .
Precipiated calcium carbonate filler (14) 16.80 :: ~-
Polyamino amide (15) 3.00 - ~
Calcium oxide filler 2.00 ~:.
Cumene hydroperoxide 0.08
Tri-basic lead sulfate heat stabilizer 1.00
20 Hydroquinone monomethyl ether 0.02
Cis - 1, 2, 3, 6 - tetrahydrophthalic anhydride 0.30
Polypropylene glycol dibenzoate plasticizer (16) 10.00
Trioctyl trimellitate plasticizer 10.00
Polyadipic acid ester plasticizer (17) 2.00
(14) AYailable from H.M. Royal as Hankuenka CC
(15) Available from Sherex Chemical Company as
Euretek 580
(16) Available from Velsicol Chemical Corporation as
Benzoflex 400
(17) Available from C.P. Hall as Plasthall P-670
.
. ~ . : :
, .. . ; . . ... . .. .
2Q il~23fi
-21-
Modifications and variations of an obvious nature
are possible without departing from the scope of the
invention as defined in the appended claims.
What is claimed is:
: ~'',:'. '
.
