U.S. patent application number 10/512802 was filed with the patent office on 2006-08-10 for surface improver for reinforced composite compositions.
This patent application is currently assigned to ASHLAND INC.. Invention is credited to CarrollG Reid, RobertL Seats.
Application Number | 20060178456 10/512802 |
Document ID | / |
Family ID | 29270729 |
Filed Date | 2006-08-10 |
United States Patent
Application |
20060178456 |
Kind Code |
A1 |
Seats; RobertL ; et
al. |
August 10, 2006 |
Surface improver for reinforced composite compositions
Abstract
The invention is a composition comprising a blend of two or more
epoxide containing compositions selected from epoxidized vegetable
oils, epoxidized alkyl esters or cycloaliphatic epoxides. In
another embodiment, the invention is a blend of one or more
epoxidized vegetable oils, epoxidized alkyl esters, or
cycloaliphatic epoxides with one or more aromatic epoxides or epoxy
functionalized polyoxyalkylene polyols.
Inventors: |
Seats; RobertL; (Powell,
OH) ; Reid; CarrollG; (Louisville, KY) |
Correspondence
Address: |
ASHLAND INC.
P.O. BOX 2219
COLUMBUS
OH
43216
US
|
Assignee: |
ASHLAND INC.
Covington
KY
|
Family ID: |
29270729 |
Appl. No.: |
10/512802 |
Filed: |
April 24, 2003 |
PCT Filed: |
April 24, 2003 |
PCT NO: |
PCT/US03/13009 |
371 Date: |
August 22, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60375944 |
Apr 25, 2002 |
|
|
|
Current U.S.
Class: |
523/500 ;
525/438 |
Current CPC
Class: |
C08K 5/1515 20130101;
C08L 63/00 20130101; C08L 63/00 20130101; C08L 2666/02 20130101;
C08L 2666/02 20130101; C08G 59/38 20130101; C08F 283/00 20130101;
C08L 67/06 20130101; C08L 67/06 20130101; C08F 283/01 20130101;
C08G 59/226 20130101 |
Class at
Publication: |
523/500 ;
525/438 |
International
Class: |
C08L 67/06 20060101
C08L067/06 |
Claims
1. An epoxy resin composition comprising a blend of two or more
epoxide compositions selected from epoxidized vegetable oil,
epoxidized alkyl esters and cycloaliphatic epoxides, or a blend of
one or more epoxide compositions selected from epoxidized alkyl
esters and cycloaliphatic epoxides with one or more epoxide
compositions selected from aromatic epoxides and polyoxyalkylene
epoxides.
2. A composition according to claim 1 which comprises from 25
percent to 75 percent by weight based on the total weight of the
epoxides of one epoxide composition and 25 percent to 75 percent by
weight of a second epoxide composition based on the weight of the
epoxide composition.
3. A composition according to claim 1 or 2 wherein one of the epoxy
compositions is an epoxidized vegetable oil.
4. A composition according to claim 3 wherein the second epoxide
composition is an epoxidized alkyl ester or a cycloaliphatic
epoxide.
5. An epoxy resin composition according to any one of claims 1 to 4
wherein the composition has an oxirane number of 8.8 or less and a
viscosity of 1000 cps (1.0 Pas) or less.
6. A surface improver for unsaturated thermosetting resin
composition which composition comprises the epoxy resin composition
according to any one of claims 1 to 7, a thermoplastic additive
comprising a thermoplastic polymer, and a compound capable of
dissolving the thermoplastic additive and epoxy composition.
7. The composition of claim 6 wherein the compound capable of
dissolving the thermoplastic resin and epoxy composition is a
crosslinking monomer capable of copolymerizing with unsaturated
thermosetting resins.
8. The composition of claim 7 wherein the thermoplastic additive is
present in an amount of 12 to 35 parts by weight, the epoxy
composition is present in an amount of 1 part to 25 parts by weight
and the crosslinking monomer is present in an amount of 40 parts to
87 parts by weight wherein there are a total of 100 parts by
weight.
9. A thermosetting resin composition comprising: a) one or more
unsaturated thermosetting resins; b) one or more crosslinking
monomers; and c) a surface improver composition according to any
one of claims 6 to 8.
10. The composition of claim 9 wherein the surface improver
composition comprises 25 to 45 parts of 100 parts of components a),
b) and c).
11. Molded parts comprising the composition of claim 9 or 10
wherein the surface of the molded object has improved surface
smoothness as compared to molded parts which do not contain part
c).
Description
[0001] The present invention relates to surface improver
compositions useful in thermosetting compositions, for instance,
unsaturated polyester and vinylester based molding compounds. It
also relates to the thermosetting compositions containing the
surface improver compositions.
[0002] Several groups of compounds have been identified as
improving the surface smoothness of molded polyester and vinyl
ester based reinforced composites. These compounds range in
composition and include epoxy compounds, polycapped oligomer
adducts of long chain fatty acids with multi hydroxy functionality
or multi epoxy functionality, and others. See Atkins U.S. Pat. No.
4,525,498. These compounds when used with thermoplastic additives,
such as polyvinyl acetate based thermoplastic compositions, improve
the shrinkage control and surface smoothness of molded polyester
and vinyl ester based reinforced composites.
[0003] Despite the improvement in surface smoothness which these
compositions impart to molded thermosetting compositions, such as
polyester and vinyl ester based reinforced composites, such molded
composites do not present as smooth a surface as metals. Thus,
there is a need for further improvement of the surface smoothness
of such molded composites.
[0004] The invention is a composition comprising a blend of two or
more epoxide containing compositions selected from epoxidized
vegetable oils, epoxidized alkyl esters or cycloaliphatic epoxides.
In another embodiment, the invention is a blend of one or more
epoxidized vegetable oils, epoxidized alkyl esters, or
cycloaliphatic epoxides with one or more aromatic epoxides or epoxy
functionalized polyoxyalkylene polyols. Reference to two or more
epoxide compositions containing compositions selected from
epoxidized vegetable oils, epoxidized alkyl esters and
cycloaliphatic epoxides means that two compositions are selected
from one, or more than one, of the listed categories. The use of
the word "composition" in this context means that the selected
material may be a mixture of compounds. In one preferred
embodiment, the epoxy composition comprises greater than 50 percent
by weight of one or more epoxy compositions comprising epoxidized
vegetable oils, epoxidized alkyl esters or cycloaliphatic epoxides
and 50 percent by weight or less of aromatic epoxides or epoxy
functionalized polyoxyalkylene polyols.
[0005] In another embodiment, the invention is an epoxy resin
composition comprising two or more epoxy resin compositions
selected from the group of epoxidized vegetable oil compositions,
epoxidized alkyl ester compositions, cycloaliphatic epoxide
compositions, aromatic epoxide compositions and polyoxyalkylene
oxide compositions wherein the composition has an average oxirane
number of 8.8 or less and a viscosity of -1000 (1.0 Pas) cps or
less
[0006] In another embodiment, the invention is a composition
comprising a blend of two or more epoxide compositions wherein at
least one is selected from epoxidized vegetable oils, epoxidized
alkyl esters, or cycloaliphatic epoxides and at least one may be
selected from an aromatic epoxide or an epoxidized polyoxyalkylene
polyol wherein the average oxirane number is 8.8 or less and the
viscosity is 1000 centipoise (1 Pas) or less.
[0007] A more preferred epoxy resin composition comprises in one
part epoxidized linseed oil and/or octyl epoxytallate and a liquid
epoxy resin. Preferably, the first part is present in an amount of
50 percent by weight or greater of the composition. In another
embodiment the epoxy composition comprises a blend of epoxidized
linseed oil and octyl epoxytallate. Preferably, the two epoxy
components are present in a weight ratio of 3:1 to 1:3, and most
preferably 1:1.
[0008] The epoxy compositions of the invention are useful as
additives in surface improvers used in unsaturated thermosetting
resin compositions, such as polyester and vinyl ester resin based
compositions.
[0009] In another embodiment the invention is a novel composition
useful as a surface improver for unsaturated thermosetting resin
compositions which composition comprises an epoxy resin composition
of this invention, a thermoplastic additive comprising a
thermoplastic polymer, preferably having a weight average molecular
weight of from 10,000 to 400,000 g/g mole; and a compound capable
of dissolving the thermoplastic additive and epoxy composition.
Preferably, such compound is a crosslinking monomer capable of
copolymerizing with unsaturated thermosetting resins.
[0010] In yet another embodiment the invention is a thermosetting
resin composition comprising:
[0011] a) one or more unsaturated thermosetting resins;
[0012] b) one or more crosslinking monomers; and
[0013] c) a surface improver composition as described herein.
[0014] Preferably the surface improver composition comprises 25
parts to 45 parts by weight and preferably 30 to 40 parts of 100
parts of components a), b) and c).
[0015] In yet another embodiment the invention comprises molded
parts comprising components a), b) and c), wherein the surface of
the molded object has improved surface smoothness as compared to
molded parts which do not contain part c).
[0016] Blends of epoxy compounds of the invention, such as a blend
of epoxidized linseed oil and octyl epoxytallate, when used in a
thermosetting composite, such as polyester or vinyl ester based
reinforced composite, provide improved surface smoothness of a
molded panel of said composition. Additionally a 50/50 blend of two
epoxy compounds provide better surface smoothness than either epoxy
compound alone or other blend ratios.
[0017] The surface improver composition comprises a thermoplastic
additive present in an amount from 12 to 35 parts by weight,
preferably from 16 to 30 parts by weight, and more preferably from
20 to 27 parts by weight; an epoxy composition present in an amount
from 12 to 25 parts by weight, preferably from 32 to 23 parts by
weight, and more preferably from 10 to 16 parts by weight; a
crosslinking monomer present in an amount from 40 to 87 parts by
weight, preferably from 47 to 81 parts by weight, and more
preferably from 57 to 70 parts by weight wherein there are 100
total parts by weight. Weights are based on the weight of the
thermoplastic additive, epoxy composition, and crossliking monomer.
Preferably, the amount of each component is chosen so as to form a
single phase system.
[0018] The unsaturated thermosetting resins suitable for use in
accordance with the present invention include those unsaturated
polymeric materials which can be crosslinked to form thermoset
articles. Typically, the unsaturated thermosetting resins have an
average molecular weight of at least 500, preferably from 500 to
10,000 grams per gram mole ("g/gmole"). As used herein the term
average molecular weight means weight average molecular weight.
Methods for determining weight average molecular weight are known
to those skilled in the art. One preferred method for determining
weight average molecular weight is gel permeation
chromatography.
[0019] Typical unsaturated thermosetting resins include, for
example, polyesters, vinyl esters, epoxy diacrylates, polyester
diacrylates, polyurethane diacrylates, acrylate capped polyurethane
polyacrylates, acrylated polyacrylates, acrylated polyethers and
the like. Especially preferred thermosetting resins include
polyesters and vinyl esters. As used herein, the term "polyesters"
includes vinyl esters. Such unsaturated thermosetting resins are
commercially available or alternatively can be readily prepared by
those skilled in the art. Examples of suitable unsaturated
thermosetting resins for use in accordance with the present
invention are described for example in U.S. Pat. Nos. 4,172,059 and
4,942,001, incorporated herein by reference.
[0020] One or more unsaturated thermosetting resins may be employed
in the molding compositions of the present invention. The total
amount of unsaturated thermosetting resins in the molding
compositions of the present invention is typically from 15 to 80
parts by weight, preferably from 20 to 60 parts by weight, and more
preferably from 25 to 50 parts by weight based on the weight of the
unsaturated thermosetting resin, thermoplastic additive, epoxide
composition and crosslinking monomer. Further details concerning
the selection and amounts of unsaturated thermosetting resins are
known to those skilled in the art.
[0021] The crosslinking monomers suitable for use in accordance
with the present invention include materials which are
copolymerizable with the unsaturated thermosetting resins. The
crosslinking monomer also serves the function of dissolving the
thermosetting resin thereby facilitating its interaction with the
other components of the molding composition. Preferably, the
monomer contains olefinic unsaturation, more preferably ethylenic
unsaturation. Typical olefinically unsaturated monomers include,
for example, styrene, vinyl toluene isomers, methyl methacrylate,
acrylonitrile and substituted styrene such as, for example,
chlorostyrene and alphamethylstyrene. Multifunctional monomers,
such as, for example, divinylbenzene or multifunctional acrylates
or methacrylates may also be employed. Styrene is a preferred
monomer for use in the compositions of the present invention. One
or more crosslinking monomers may be used in the molding
compositions of the present invention. Typically, the total amount
of the crosslinking monomer is from 20 to 80 parts by weight,
preferably from 30 to 65 parts by weight, and more preferably from
40 to 55 parts by weight based on the weight of the unsaturated
thermosetting resin, thermoplastic additive, epoxy resin
composition and crosslinking monomer. Such monomers are readily
commercially available. Further details concerning the selection
and amounts of the crosslinking monomers are known to those skilled
in the art.
[0022] One or more thermoplastic additives may be employed in the
molding compositions of the present invention. Typically, the total
amount of the thermoplastic additive is from 3 to 30 parts,
preferably from 5 to 25 parts, and more preferably from 8 to 20
parts based on the weight of the unsaturated thermosetting resin,
thermoplastic additive, epoxide composition and crosslinking
monomer. Examples of the thermoplastic additives suitable for use
in accordance with the present invention are described, for
example, in U.S. Pat. No. 4,172,059, incorporated herein by
reference. Such thermoplastic additives are commercially available
or alternatively can be prepared by those skilled in the art.
Further details concerning the selection and amounts of the
thermoplastic additives are known to those skilled in the art.
[0023] The average molecular weights of the thermoplastic additives
of the present invention are 10,000 g/gmole or greater, preferably
25,000 or greater, more preferably from 50,000 or greater and most
preferably 80,000 or greater. The average molecular weights are
preferably 400,000 g/gmole or less, more preferably 300,000 or
less, even more preferably 250,000 or less and most preferably
200,000 or less. These thermoplastic additives can be used in
conjunction with lower molecular weight materials which can enhance
their shrinkage control ability such as epoxies, lower reactivity
secondary monomers and others. Examples of such approaches are
disclosed in U.S. Pat. Nos. 4,525,498, 4,755,557, and 4,374,215,
incorporated herein by reference.
[0024] The epoxy compounds of this invention can be based on
aliphatic, cycloaliphatic, or aromatic backbones. Preferred epoxy
resins are liquid at room temperature. One class of preferred epoxy
resins are epoxidized vegetable oils. Vegetable oils are naturally
occurring triglycerides (triesters of glycerol and mixed
unsaturated fatty acids). Among preferred vegetable oils are
linseed oil, soybean oil, safflower oil, corn oil, cottonseed oil,
rapeseed oil and peanut oil. These oils can be epoxidized at
unsaturated sites to produce epoxidized vegetable oils using
processes well known to those of average skill in the art. More
preferred vegetable oils are soybean and linseed oil, with linseed
oil most preferred. Synthetic versions or refined versions of these
epoxidized vegetable oils may be used in the invention.
[0025] Epoxidized alkyl esters are epoxidized versions of natural
esters of fatty acids. Preferred epoxidized alkyl esters are
derived from alkyl esters of oleic or tall oil fatty acids or from
alkyl epoxy stearates. A more preferred class are the epoxidized
tall oil fatty acids, commonly referred to epoxy tallates.
Synthetic or refined versions of epoxidized alkyl esters may be
used in this invention.
[0026] Cycloaliphatic epoxides as used herein refer to epoxy
compositions containing compounds having cycloaliphatic resins with
an oxirane ring attached or fused to the cycloaliphatic ring.
Preferably, the oxirane ring is fused to the cycloaliphatic ring. A
more preferred cycloaliphatic ring is an epoxy cyclohexane (epoxy
cyclohexyl) which is represented by the formula ##STR1##
[0027] Preferred cycloaliphatic epoxide containing compositions
contain compounds with an average of one or more, preferably on
average of two or more cycloaliphatic moieties with epoxide groups
fused or attached. Among preferred cycloaliphatic epoxides are
3,4-Epoxycyclohexylmethyl 3,4-epoxycyclohexane-carboxylate,
available from The Dow Chemical Company under the trade designation
ERL-4221E; bis(3,4-epoxycyclohexyl methyl) adipate available from
The Dow Chemical Company under the trade designation ERL-4299 and
1,2-Epoxy-4-vinylcyclohexane available from The Dow Chemical
Company.
[0028] Aromatic epoxides as used herein refer to compositions
containing compounds having aromatic moieties with epoxide moieties
attached thereto. Among preferred aromatic epoxides are novolac and
bisphenol based aromatic epoxides. Representative of preferred
bisphenol resins useful in this invention are those disclosed in
U.S. Pat. No. 5,308,895 at column 8, line 6 and represented by
Formula 6. Relevant portions of such patent are incorporated herein
by reference. Preferably, the aromatic epoxide is a liquid epoxy
resin. The most preferred aromatic epoxy resins are bisphenol-A and
bisphenol-F based epoxy resins.
[0029] The epoxide terminated polyoxyalkylene polyols comprise
compositions containing compounds wherein a polyoxyalkylene chain
is functionalized with one or more epoxide moieties. The
polyoxyalkylene chains are preferably prepared from one or more
alkylene oxides. Representative examples of polyalkylene based
epoxy resins are those described in U.S. Pat. No. 5,308,895 at
column 8, line 9 and formula 9 and the description thereof
following. Relevant portions of such description are incorporated
herein by reference. Preferably, the polyoxyalkylene epoxide is
derived from an ethylene oxide, propylene oxide or a mixture
thereof.
[0030] In one embodiment, the compositions of the invention
preferably comprise a mixture of two or more epoxide compositions
where at least two are selected from different groups comprising
epoxidized vegetable oils, epoxidized alkyl esters and
cycloaliphatic epoxides. A most preferred blend is a blend of an
epoxidized vegetable oil and an epoxidized alkyl ester. Preferably,
at least one of the epoxides in the composition is an epoxidized
vegetable oil. Preferably, all of the epoxides contained in the
compositions are selected from epoxidized vegetable oil, epoxidized
alkyl esters and cycloaliphatic epoxides. More preferably, the
blend of epoxides used contains an epoxidized vegetable oil and
most preferably epoxidized linseed oil.
[0031] It has been discovered that a blend of epoxides which have
an oxirane number of 8.8 or less and a viscosity of 1000 centipoise
or less exhibits a surface waviness which is at least 10 percent
lower, than if either or both of the epoxide compositions exhibit
an oxirane number is greater than 8.8 and viscosity which is
greater than 1000 centipoise.
[0032] Preferably, the blend of epoxide compositions comprises at
least 25 percent by weight of at least 2 epoxide compositions,
based on the weight of the epoxide compositions, and more
preferably 33 percent by weight of at least two epoxide
compositions and most preferably 45 percent by weight or greater
least two epoxide compositions. Preferably, the epoxide composition
blend contains no more than 75 percent of one of the epoxide
compositions, based on the weight of the epoxide compositions, and
more preferably no more than 67 percent by weight of one epoxide
composition and even more preferably no more than 55 percent by
weight or less. In a most preferred embodiment, the epoxide blend
is a blend of 50 percent of one epoxide composition and 50 percent
of a second epoxide composition.
[0033] The preferred concentration of total epoxy compounds is 1 to
25 parts per hundred parts of the epoxy composition thermosetting
resin, crosslinking monomer and thermoplastic additive, more
preferred 2 to 10 parts per hundred parts and even more preferred 3
parts to 8 parts per hundred parts.
[0034] Thickening agents may also be employed in the compositions
of the invention. Such materials are known in the art and include
the oxides and hydroxides of the metals of Group I, II and III of
the Periodic Table. Examples of preferred thickening agents include
magnesium oxide, calcium oxide, calcium hydroxide, zinc oxide,
barium oxide, magnesium hydroxide and the like, including mixtures
of the same. Thickening agents are normally employed in proportions
of from bout 0.1 to 6 weight percent based on the weight of the
thermosetting resin, crosslinking monomer, thermoplastic additive
and epoxide composition.
[0035] Alternatively, a dual thickening system may be employed
wherein, for example, a metallic oxide or hydroxide and
polyisocyanate in amounts of polyisocyanate sufficient to react
with at least thirty percent of the hydroxyl groups but not more
than one hundred and five percent of the hydroxyl groups present
and an amount of metallic oxide or hydroxide sufficient to react
with at least thirty percent of the carboxyl groups but not more
than seventy-five percent of the carboxyl groups present.
[0036] The fiber reinforcements which are often employed in the
molding compositions of the invention can be, for example, any of
those known to the art for use in molding compositions. Examples of
such materials are glass fibers or fabrics, carbon fibers and
fabrics, asbestos fibers or fabrics, various organic fibers and
fabrics such as those made of polypropylene, acrylonitrile/vinyl
chloride copolymer, and others known to the art. These reinforcing
materials are typically employed in the molding compositions at a
level of from 5 to 80 weight parts, based on the total weight of
the composition and preferably 15 to 50 weight parts.
[0037] In addition to the above-described ingredients, the molding
compositions of the present invention also frequently contain
pigment. The amount of pigment may vary widely, depending on the
particular molding composition and pigment used. The pigment is
typically employed in the range of 0.5 to 15 weight parts based on
the total weight of the composition.
[0038] The molding compositions of the invention may also contain
one or more other conventional additives, which are employed for
their known purposes in the amounts known to those skilled in the
art. The following are illustrative of such additives:
[0039] 1. Polymerization initiators such as t-butyl hydroperoxide,
t-butyl perbenzoate, benzoyl peroxide, t-butyl peroctoate, cumene
hydroperoxide, methyl ethyl ketone peroxide, peroxy ketals, and
others known to the art, to catalyze the reaction between the
olefinically unsaturated monomer and the thermosetting resin. The
polymerization initiator is employed in a catalytically effective
amount, such as from 0.3 to 3 parts, based on the weight of the
unsaturated thermosetting resin, thermoplastic additive, and
crosslinking monomer.
2. Fillers such as clay, alumina trihydrate, silica, calcium
carbonate, and others known to the art;
3. Mold release agents or lubricants, such as zinc stearate,
calcium stearate, and others known to the art, and
4. Water.
[0040] One especially preferred molding composition in accordance
with the present invention comprises:
(i) from 20 to 60, preferably 27 to 35, weight parts based on the
weight of the unsaturated thermosetting resin, thermoplastic
additive, and crosslinking monomer of an unsaturated polyester and
epoxide composition;
[0041] (ii) from 30 to 65, preferably 47 to 55, weight parts based
on the weight of the unsaturated thermosetting resin, thermoplastic
additive, epoxide composition and crosslinking monomer of an
olefinically unsaturated monomer which is copolymerizable with the
unsaturated polyester;
[0042] (iii) from 5 to 25, preferably 10 to 14, weight parts based
on the weight of the unsaturated thermosetting resin, thermoplastic
additive, epoxy composition and crosslinking monomer of a polyvinyl
acetate homopolymer or copolymer having a weight average molecular
weight of from 70,000 or greater, more preferably 80,000 g/gmole or
greater and preferably 250,000 or less and more preferably 200,000
grams per gram mole or less and;
(iv) from 2 to 10, preferably 3 to 8, weight parts based on the
weight of the unsaturated thermosetting resin, thermoplastic
additive, epoxy composition and crosslinking monomer.
[0043] The molding compositions of the present invention can be
prepared by methods known to those skilled in the art, such as for
example, mixing the components in a suitable apparatus such as
Hobart mixer at temperatures on the order of 20.degree. C. to
50.degree. C. The components may be combined in any convenient
order. Generally, it is preferable that the thermosetting resin and
thermoplastic additive are added in liquid form by preparing a
solution thereof in the crosslinking monomer. All the liquid
components are then typically mixed together before adding the
fillers, thickening agents and optional ingredients.
[0044] Once formulated, the molding compositions can be molded into
thermoset articles of the desired shape, for example, automotive
fenders, hoods, bathtubs, doors, and the like. The specific
conditions used in the molding process depend on the composition
being molded as well as upon the nature of the particular articles
desired, the details of which are known to those skilled in the
art.
[0045] The molding compositions are suitable for use, for example,
as sheet molding compounds and bulk molding compounds, with sheet
molding compounds being more typical. For example, sheet molding
compound can be produced by laying down a first layer of the
molding composition, that is, paste, on a first layer of
polyethylene film or the equivalent thereof, laying on this first
layer of the paste filler reinforcements such as chopped glass
fibers, and laying thereover a second layer of the paste. The two
layers of the paste with the filler reinforcements sandwiched
therebetween are then topped with a second sheet of polyethylene
film and the resulting composite (sheet molding compound) is
stored. Further details concerning the manufacture, handling and
use of sheet molding compounds and bulk molding compounds are known
to those skilled in the art.
[0046] The following examples are provided for illustrative
purposes and are not intended to limit the scope of the claims
which follow. All parts and percentages are by weight unless
otherwise specified.
[0047] The following materials and terms were used in the examples
set forth below:
Glossary
[0048] S342 is a highly reactive unsaturated polyester resin sold
by Alpha Owens Corning and is used for automotive SMC
applications.
[0049] BMC stands for bulk molding composition.
[0050] CM-2015 is a 35 percent carbon black pigment dispersion
available from Plasticolors, Inc., Ashtabula, Ohio.
[0051] Modifier E is a 5 percent solution of parabenzoquinone in
diallylphthalate.
[0052] Luperox P is a 98 percent solution of t-butylperoxy benzoate
sold by Elf Atochem North America, Philadelphia Pa.
[0053] VR-3 is a viscosity reducer for SMC/BMC sold by The Dow
Chemical Company, Midland Mich.
[0054] Maglite D is a technical grade magnesium oxide sold by
Marine Magnesium Company LPA refers to low profile additive.
[0055] Neulon G is a proprietary carboxylated poly(vinyl acetate)
manufactured and sold by The Dow Chemical Company, Midland,
Mich.
[0056] LP-90 is a 40 percent solution of poly(vinyl acetate)
homopolymer dissolved in styrene and sold by The Dow Chemical
Company, Midland Mich.
[0057] Hubercarb W4 is a calcium carbonate of 5 micron particle
size sold by J. M. Huber Company.
[0058] SMC stands for sheet molding compound.
[0059] SWI stands for surface waviness index as measured by a
Diffracto D-sight audit station produced and sold by Diffracto
Ltd.
[0060] UPE stands for unsaturated polyester.
[0061] ON stands for oxirane number.
[0062] A-Paste is the portion of the formulation containing either
some or all of the thermosetting resin, the crosslinking monomer,
the thermoplastic additive, the polymerization initiators, the mold
release agents, the pigments, the filler, etc.
[0063] B-Paste is the portion of the formulation containing either
some or all of the vehicle, the pigment, the crosslinking monomer,
the thickeners, the filler, etc.
[0064] PPG 5509 is a fiber glass reinforcement sold by PPG
Industries.
Procedure for Preparation of Sheet Molding Compound (SMC)
Formulations
[0065] All the liquid components were weighed individually into a
five gallon open top container placed on a Mettler balance. The
contents of the container were then mixed with a high speed Cowles
type dissolver. The agitator was started a slow speed, then
increased to medium speed to completely mix the liquids over a
period of 2-3 minutes. The mold release agent was next added to the
liquids and mixed until completely dispersed. The filler was next
added gradually until a consistent paste was obtained and the
contents were then further mixed to a minimum temperature of
90.degree. F. (32.degree. C.). The thickening agent was next mixed
into the paste over a period of 2-3 minutes. The paste was next
added to doctor boxes on a sheet molding compound (SMC) machine
where the paste is metered into a film on the carrier sheet where
it is further combined with fiber glass (1 inch (2.54 cm) fibers).
The sheet molding compound was then allowed to mature to molding
viscosity.
Preparation of Molding Test Panels
[0066] Flat panels for surface evaluation were molded on a 200 ton
(8181 metric ton) Lawton press containing a matched die set of 18''
by 18'' (47.times.47 cm) chrome plated molds. The female cavity is
installed in the bottom and the male portion is at the top. Both
molds are hot oil heated and are controlled so that they can be
operated at different temperatures. For the present molding, the
top and bottom temperatures were 295.degree. F. to 305.degree. F.
(146 to 151.degree. C.). 1200 g samples of molding compound were
employed, and the molded part thickness was 0.120'' (0.30 cm). The
molding pressure, which can be varied from 0 to 1000 psi (0 to 6895
kPa), was run at maximum pressure. The panels were laid on a flat
surface, weighted to keep them flat, and allowed to cool
overnight.
Procedure for Determining Surface Smoothness of Molded Panels
[0067] Surface quality measurements were performed on a Diffracto
D-sight Audit Station-2 manufactured and sold by the Diffracto Co.,
Ltd. The surface waviness index (SWI) provided by this instrument
is the standard deviation of the panel's surface with regard to
long term waviness, as compared to the surface of a perfectly flat
panel, whose long term waviness is zero. The smaller the SWI
number, the smoother the panel.
EXAMPLE 1
[0068] Table 1 showed SMC formulations utilizing epoxidized linseed
oil, octyl epoxytallate, and blends of the same. In Table 1 all
numbers were parts by weight. In preparing the SMC, 72 percent of
the composition described was blended with 28 percent by weight of
PPG 5509 glass fibers. The B side comprised LP-90, 29.90 percent;
Styrene, 12.80 percent; Maglite D, 9.90 percent, CM-2015, 0.50
percent and Hubercarb W4, 46.90 percent. Table 2 showed the surface
waviness index of the molded panels as determined on the Diffracto
D-sight audit station. The 50/50 blend of the epoxy compounds gave
a smoother surface (lower surface waviness index) than either epoxy
compound alone or at other blend ratios. TABLE-US-00001 TABLE 1 SMC
Formulations Utilizing Epoxy Compounds 1 2 3 4 5 S342 55 55 55 55
55 Neulon-G 35 35 35 35 35 Styrene 10 10 10 10 10 Epoxidized 0 1.5
3 4.5 6 linseed oil Octyl 6 4.5 3 1.5 0 epoxytallate Modifier E 0.4
0.4 0.4 0.4 0.4 Luperox P 1.8 1.8 1.8 1.8 1.8 Zinc Stearate 2.5 2.5
2.5 2.5 2.5 VR3 2 2 2 2 2 Hubercarb 215 215 215 215 215 W4 B-Side
7.3 7.3 7.3 7.3 7.3 LP-90 29.9 percent Styrene 12.8 percent Maglite
D 9.9 percent CM-2015 0.5 percent Hubercarb 46.9 percent W4 PPG
5509 28 percent 28 percent 28 percent 28 percent 28 percent
[0069] TABLE-US-00002 TABLE 2 Surface Waviness Index of
Formulations in Table 1 Octyl Epoxidized epoxytallate, Waviness
linseed oil, pts pts Index 0 6 272 1.5 4.5 222 3 3 184 4.5 1.5 213
6 0 273
[0070] Several samples were prepared and tested for surface
waviness as described hereinbefore. The oxirane number was
determined on each sample according to the procedure described in
ASTM D1652 Standard Test Methods for Epoxy Content of Epoxy Resins,
Test Method B. The viscosity was determined using a Brookfield
viscometer at ambient temperature. The results were compiled in
Table 3. TABLE-US-00003 TABLE 3 Visc. Epoxide SWI (cps) (Pa s) ON
Octyl Epoxy Tallate.sup.1 272 27 0.027 4.6 Octyl Epoxy Ester.sup.2
214 32.5 (0.0325) 5.77 Octyl Epoxy Tallate.sup.1/Bisphenol 222 160
(0.160) 6.3 based epoxy resin 1.sup.3 Octyl Epoxy
Tallate.sup.1/Bisphenol 227 100 (0.100) 6.65 based epoxy resin
2.sup.4 Epoxidized Linseed Oil/Octyl 184 128 (0.128) 7.1 Epoxy
Tallate.sup.1 Epoxidized Linseed Oil.sup.5/Octyl 160 85 (0.085)
7.71 Epoxy Ester.sup.2 Octyl Epoxy Tallate.sup.1/ 208 70 (0.070)
8.1 Cycloaliphatic epoxide.sup.6 Bisphenol based epoxy resin
1.sup.3 275 16100 16.100 8.2 Bisphenol based epoxy resin 3.sup.7
231 13700 13.700 8.4 Bisphenol based epoxy resin 224 11700 11.700
8.7 1.sup.3/Bisphenol based epoxy resin 4.sup.8 Bisphenol based
epoxy resin 347 8500 8.500 8.9 1.sup.3/Bisphenol based epoxy resin
2.sup.4 Bisphenol based epoxy resin 2.sup.4 241 6800 6.800 9
Bisphenol based epoxy resin 4.sup.9 199 11500 11.500 9 Epoxidized
Linseed Oil.sup.5/Bisphenol 209 1430 1.430 9.33 based epoxy resin
1.sup.3 Bisphenol based epoxy resin 2.sup.4 232 1210 1.210 9.35
Epoxidized Linseed Oil.sup.5 273 682 .682 9.648 Epoxidized Linseed
Oil.sup.5/ 196 502 .502 10.6 Cycloaliphatic epoxide.sup.6
Cycloalihatic epoxide.sup.6 263 337 .337 11.6 .sup.1Available from
Witco under the trademark DRAPEX 4.4. .sup.2Available from Atofina
under the trademark VIKOFLEX 4050. .sup.3Available form The Dow
Chemical Company under the Trademark and designation DER 331 and
was a standard, nondiluted, low molecular weight liquid epoxy resin
having an EEW of 182-192 .sup.4Available form The Dow Chemical
Company under the Trademark and designation DER 332 and was a low
epoxide equivalent weight, high purity diglycidyl ether of
bisphenol-A. Low viscosity and color having an EEW of 171-175.
.sup.5Available from The Dow Chemical Company under the trademark
FLEXOL LOE. .sup.63,4-epoxycyclohexylmethyl
3,4-epoxycylohexane-carboxylate available form The Dow Chemical
Company under the Trademark and designation ERL-4221.
.sup.7Available form The Dow Chemical Company under the Trademark
and designation DER 383 which is low viscosity liquid epoxy resin
having an EEW of 176-183. .sup.8Available form The Dow Chemical
Company under the Trademark and designation DER 330, which is low
viscosity, undiluted, low epoxide equivalent weight liquid epoxy
resin having an EEW of 176-185. EEW means epoxy equivalent
weight.
[0071] Table 3 illustrated that compositions containing blends of
epoxidized vegetable oils, epoxy alkyl esters and cycloaliphatic
epoxides with one another and with aromatic epoxides demonstrated
lower surface waviness indices than compositions containing an
individual class of epoxides. Data from Table 3 was represented
below to better illustrate this. TABLE-US-00004 SWI Octyl Epoxy
Ester 214 Blend 160 Epoxidized LO 273 Bisphenol-A Epoxy1.sup.3 275
Blend 209 Epoxidized LO 273 Bisphenol-A Epoxy2.sup.4 241 Blend 232
Epoxidized LO 273 Octyl Epoxy Tallate 272 Blend 184 Epoxidized LO
273 Bisphenol-A Epoxy1.sup.3 275 Blend 222 Octyl Epoxy Tallate 272
Bisphenol-A Epoxy2.sup.4 241 Blend 227 Octyl Epoxy Tallate 272
Bisphenol-A Epoxy1.sup.3 241 Blend 347 Bisphenol-A Epoxy2.sup.4 275
Epoxidized linseed oil 273 Blend 196 Cycloaliphatic epoxide 263
Octyl epoxy tallate 272 Blend 208 Cycloaliphatic epoxide 263
[0072] The data in Table 3 was statistically analyzed to examine
two parameters, first epoxide oxirane number greater than 8.8 and
less than 8.8 and second viscosity less than 1000 cps (1.0 Pas) and
greater than 1000 cps (1.0 Pas). The average surface waviness index
of formulations containing epoxides and epoxide blends meeting
these criteria were segregated into four groups based on these
criteria and averaged. The results were shown below. TABLE-US-00005
Average Surface Waviness (SWI) Epoxide(s) Greater than 245 246
Oxirane 8.8 Number Less Than 213 243 8.8 Less Than Greater Than
1000 1000 (1.0 Pa s) (1.0 Pa s) Epoxide(s) Viscosity, cps
[0073] These data demonstrated that a blend of epoxides having an
oxirane number of 8.8 or less and a viscosity of 1000 cps (1.0 Pas)
or less gave the best surface waviness index numbers.
* * * * *