Polystyrene modified advanced epoxy resin and polyester copolymers

Advanced epoxy resin and polyester blends suitable for use in powder coatings are prepared by (I) polymerizing, in the presence of a suitable catalyst such as tertiary butyl perbenzoate, (A) the reaction product of (1) a diglycidyl ether of a dihydric phenol such as the diglycidyl ether of bisphenol A and with (2) a compound containing a group reactive with an epoxide group and a polymerizable ethylenically unsaturated group such as methacrylic acid; with (B) a monomer feed containing (1) at least one vinyl aromatic monomer such as styrene; (2) a compound containing a group reactive with an epoxide group and a polymerizable ethylenically unsaturated group such as methacrylic acid; and optionally (3) a hydroxyalkyl acrylate or methacrylate or an alkyl acrylate or methacrylate such as hydroxyethylacrylate; and (II) advancing, in the presence of a suitable advancement catalyst such as ethyltriphenylphosphonium acetate acetic acid complex, the resultant polymerized product with (C) a dihydric phenol such as bisphenol A and (III) combining the resulting advanced epoxy resin from step (II) with (D) an acid and/or hydroxyl functional polyester in an amount sufficient to provide a mole ratio of epoxide groups to acid and/or hydroxyl groups of from about 0.9 to 1 to about 1.1 to 1.

BACKGROUND OF THE INVENTION 
Copolymerization of advanced epoxy resins and polyesters containing 
hydroxyl or carboxylic acid groups is well known to the prior art to 
provide cured decorative powder coatings. Said powder coatings possess 
many usable properties, however, deficiencies in aqueous corrosion 
resitance to both acid and alkali are frequently apparent thus limiting 
their use. 
The present invention provides polystyrene modified advanced epoxy resin 
and polyester copolymers with improved aqueous corrosion resistance to 
both acid and alkali, as well as improved reactivity while maintaining 
other properties such as, for example, impact resistance. 
SUMMARY OF THE INVENTION 
One aspect of the present invention pertains to an advanced epoxy resin and 
polyester blend which comprises the product resulting from 
(I) polymerizing in the presence of a catalytic quantity of a suitable 
polymerization catalyst 
(A) the reaction product of 
(1) at least one diglycidyl ether of a dihydric phenol with 
(2) at least one compound containing a group relatively with an epoxide 
group and a polymerizable ethylenically unsaturated group in an amount of 
from about 0.001 to about 0.05, preferably from about 0.005 to about 
0.025, equivalent per epoxide equivalent contained in component (A-1); 
with 
(B) a monomer feed containing 
(1) at least one vinyl aromatic monomer in an amount of from about 31 to 
about 60, preferably from about 35 to about 45, percent by weight of the 
total weight of components (A), (B) and (C); 
(2) at least one compound containing a group reactive with an epoxide group 
and a polymerizable ethylenically unsaturated group in an amount of from 
about 0.001 to about 0.05, preferably from about 0.005 to about 0.025, 
equivalent per epoxide equivalent contained in component (A-1); and 
optionally 
(3) a hydroxyalkyl acrylate or methyacrylate or an alkyl acrylate or 
methacrylate or any combination thereof in an amount of from about zero to 
about 15, preferably from about 1 to about 5, percent by weight based on 
total weight of components (B-1) and (B-3); and 
(II) advancing, in the presence of a catalytic quantity of a suitable 
advancement catalyst, the polymerized product from step (I) with 
(C) at lest one dihydric phenol in an amount of from about 0.125 to about 
0.80, preferably from about 0.375 to about 0.50 hydroxyl equivalents per 
epoxide equivalent contained in component (A-1); and 
(III) combining the advanced epoxy resin from step (II) with 
(D) at least one acid functional polyester or hydroxyl functional polyester 
or a combination thereof in an amount sufficient to provide a mole ratio 
of epoxide groups contained in the product produced in step (II) to acid 
and/or hydroxyl groups of from about 0.9:1 to about 1.1:1. 
Another aspect of the present invention concerns powder coating 
compositions and other products resulting from curing the aforementioned 
advanced epoxy resin and polyester blends. 
DETAILED DESCRIPTION OF THE INVENTION 
Suitable diglycidyl ethers of a dihydric phenol which can be employed 
herein include, for example, those represented by the formulas 
##STR1## 
wherein A is a divalent hydrocarbon group having from one to about 10 
carbon atoms, 
##STR2## 
each X is independently hydrogen, bromine, chlorine, or a hydrocarbyl or 
hydrocarbyloxy group having from 1 to about 10 carbon atoms; each R is 
independently hydrogen or a methyl group; m has a value from zero to about 
5, preferably from about zero to about 3 and n has a value of zero or 1. 
The term hydrocarbyl as employed herein means any aliphatic, 
cylcoaliphatic, aromatic, aryl substituted aliphatic, or aliphatic 
substituted aromatic groups. Likewise, the term hydrocarbyloxy group means 
a hydrocarbyl group having an oxygen linkage between it and the object to 
which it is attached. 
Suitable diglycidyl ethers of a dihydric phenol which can be employed 
herein include, for example, the diglycidyl ethers of resorcinol, 
hydroquinone, catechol, bisphenol A (4,4'-isopropylidenediphenol), 
bis(4,4'-dihydroxyphenyl)methane, 2,2'-bis(4-hydroxyphenyl)pentane, 
3,3',5,5'-tetramethyl-4,4'-dihydroxydiphenyl, 4,4'-dihydroxydiphenyl 
sulfone, 4,4'-dihydroxybenzophenone, 
3,3',5,5'-tetrabromo-4,4'-isopropylidenediphenol, 
4,4'-bis(p-hydroxyphenyl)diphenyl ether, 4,4'-dihydroxydiphenyl sulfide, 
mixtures thereof and the like. Most preferred as the diglycidyl ether of a 
dihydric phenol are the diglycidyl etheres of bisphenol A. 
Suitable compounds which contain both a group reactive with an epoxide 
group and a polymerizable ethylenically unsaturated group include 
compounds wherein said group reactive with an epoxide group is a compound 
containing a carboxylic acid, hydroxyl or amido group. Suitable compounds 
which contain both a group reactive with an epoxide group and a 
polymerizable ethylenically unsaturated group include, for example, the 
acrylic acids, such as, for example, acrylic acid and methacrylic acid the 
monoesters of .alpha., .beta.-unsaturated dicarboxylic acids, such as 
monomethyl maleate and monobutylfumarate; the alkenylphenols such as, for 
example, p-isopropenylphenol and m-vinylphenol; the hydroxyalkyl acrylates 
such as, for example, 2-hydroxyethyl acrylate, 2-hydroxyethyl 
methacrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl methacrylate, 
2-hydroxybutyl acrylate, 2-hydroxybutyl methacrylate and the acrylamides 
such as, for example, methacrylamide and acrylamide, any combination 
thereof and the like. Most preferred as the compound containing a group 
reactive with an epoxide group and a polymerizable ethylenically 
unsaturated group is methacrylic acid. 
The prereaction (step A) of the diglycidyl ether of a dihydric phenol and a 
compound which contains both a group reactive with an epoxide group and a 
polymerizable ethylenically unsaturated group is performed at a 
temperature of from about 75.degree. to about 200.degree. C., preferably 
from about 140.degree. to about 160.degree. C. for from about 15 (900 s) 
to about 150 minutes (9000 s), preferably for from about 30 (1800 s) to 
about 60 minutes (3600 s). The prereaction step times and temperatures 
vary as a function of the type of compound which contains both a group 
reactive with an epoxide group and a polymerizable ethylenically 
unsaturated group that is used. 
A catalyst may optionally be employed to facilitate reaction of the group 
reactive with an epoxide group and the epoxide group. Generally, a 
catalyst is not required and, furthermore, is not desired when said group 
reactive with an epoxide group is --COOH. It may, however, be beneficial 
to use a catalyst when said group reactive with an epoxide group is, for 
example, --OH. Typical of such catalysts useful for this purpose are the 
advancement catalysts described herein. 
Suitable vinyl aromatic monomers which can be employed as component (B-1) 
in the copolymerization reaction step with the prereaction product of a 
diglycidyl ether of a dihydric phenol and a compound containing both a 
group reactive with an epoxide group and a polymerizable ethylenically 
unsaturated group include those represented by the formula 
##STR3## 
wherein R and X are as hereinbefore defined. 
Representative of the vinyl aromatic monomers which can be employed herein 
are, for example, styrene, chlorostyrenes, methylstyrenes, 
t-butylstyrenes, .alpha.-methylstyrene, methoxystyrenes, mixtures thereof 
and the like. Most preferred as the vinyl aromatic monomer is styrene. 
Suitable hydroxyalkyl acrylates or methacrylates, alkyl acrylates or 
methacrylates or mixtures thereof which can be employed as component (B-3) 
in the copolymerization reaction step with the prereaction product of a 
diglycidyl ether of a dihydric phenol and a compound containing both a 
group reactive with an epoxide group and a polymerizable ethylenically 
unsaturated group include, for example, hydroxyalkyl acrylates or 
methacrylates, alkyl acrylates or methacrylates or mixtures thereof. The 
specific amount and type of said acrylates or methacrylates may be chosen 
so as to effect the final properties of a cured powder coating. Small 
amounts (about 0.25 to about 2 percent by weight based on total weight of 
monomer feed used) of a hydroxyalkyl acrylate or methacrylate are used to 
increase adhesion of the powder coating to metal substrates. Larger 
amounts (about 2.1 to about 15 percent by weight based on total weight of 
monomer feed used) of a hydoyalkyl acrylate or methacrylate increase the 
gloss of the powder coating. The alkyl acrylates or methacrylates, 
especially those possessing 8 or more carbon atoms, are used in small 
amounts (about 1 to about 5 percent by weight based on taotal weight of 
monomer feed used) to decrease the glss of the powder coating. Larger 
amounts (about 5.1 to about 15 percent by weight based on total weight of 
monomer feed used) of certain alkyl acrylates or methacrylates can be used 
to also impart modified texture to the powder coating. Combinations of 
said acrylates and methacrylates may also be used. Specific hydroxyalkyl 
acrylates or methacyrlates, alkyl acrylates or methacrylates which can 
optionally be employed herein include those represented by the formula 
##STR4## 
wherein R is as hereinbefore defined and Q is a monovalent hydrocarbyl 
group having from one to about 25 carbon atoms or a hydroxyalkyl group 
having from two to about 25 carbon atoms and may be branched, cyclic or 
polycyclic. Representative of the hydroxyalkyl acrylates or methacyrlates, 
alkyl acrylates or methacrylates or mixtures thereof which can optionally 
be employed herein are, for example, 2-hydroxyethyl acrylate, 
2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxybutyl 
acrylate, 2-hydroxybutyl methacylate, cyclohexyl acrylate, lauryl 
methacrylate, stearyl acrylate, mixtures thereof and the like. 
Suitable free radial forming catalysts which can be employed in the 
copolymerization reaction step with the prereaction product of a 
diglycidyl ether of a dihydric phenol and a compound containing both a 
group reactive with an epoxide group and a polymerizable ethylenically 
unsaturated group include the azo and diazo compounds as well as the 
organic peroxides and hydroperoxides. Suitable free radical forming 
catalysts include, for example, 2,2'-azobisisobutyronitrile, 
2,2'-azobis(2,4-dimethyl-4-methoxyvaleronitrile), 
1-t-butylazo-1-cyanocyclohexane, t-butylperbenzoate, t-butylperoctoate, 
t-butylhydroperoxide, di-t-butylperoxide, dicumylperoxide, cumene 
hydroperoxide, mixtures thereof and the like. An amount of from about 1.0 
to about 5.0, preferably from about 2.0 to about 3.0 percent by weight, 
based on total weight of monomer feed used, of at least one free radical 
forming catalyst is employed. 
The copolymerization reaction of the prereaction product (A) of a 
diglycidyl ether of a dihydric phenol and a compound containing both a 
group reactive with an epoxide group and a polymerizable ethylenically 
unsaturated group with a monomer feed consisting of (B-1) a vinyl aromatic 
monomer, (B-2) a compound containing both a group reactive with an epoxide 
group, and a polymerizable ethylenically unsaturated group, and 
optionally, (B-3) a hydroxyalkyl acrylate or methacrylate, an alkyl 
acrylate or methacrylate, or a mixture thereof may be completed using a 
variety of reaction sequences. Generally, the monomer feed (B) containing 
a free radial forming polymerization catalyst is added to the prereaction 
product (A) over a period of from about 45 minutes (2700 s) to about 150 
minues (9000 s), preferably from about 75 minutes (4500 s) to about 120 
minutes (7200 s) while maintaining a reaction temperature of from about 
125.degree. to about 175.degree. C., preferably from about 140.degree. to 
about 160.degree. C. A post reaction of from about 30 minutes (1800 s) to 
about 150 minutes (9000 s), preferably from about 45 minutes (2700 s) to 
about 90 minutes (5400 s) is completed after completion of the monomer 
feed addition. 
It is necessary to maintain an inert atmosphere throughout the 
copolymerization reaction. This is achieved by blanketing the reaction 
mixture with nitrogen, argon or some other inert gas. Adequate stirring is 
required to intimately mix and disperse the reactants. 
In an equally preferred process of the present invention, the free radical 
forming catalyst may be removed as a component of the monomer feed and 
added to the reaction mixture separately. If this is done, it is generally 
desirable to maintain concurrent addition of the free radical forming 
catalyst and the remaining monomer feed (B-1, B-2 and, optionally, B-3). 
The rate of this concurrent addition should be adjusted such that an 
excess of unpolymerized monomer feed does not accumulate. 
As a further embodiment of the present invention, a portion of free radical 
forming catalyst may be added to the reaction mixture at the end of the 
monomer feed addition, more preferably about 15 minutes (900 s) to about 
120 minutes (7200 s) after completion of the monomer feed addition. This 
is done if unpolymerized monomer feed is present and allows for completion 
of the copolymerization reaction. 
The advancement reaction of the aforementioned copolymerization product of 
(A) and (B) with a dihydric phenol is performed in the presence of an 
advancement catalyst. Suitable dihydric phenols include, for example, 
those represented by the formulas 
##STR5## 
wherein X, A and n are as hereinbefore defined. Representative of the 
bisphenols are resorcinol, hydroquinone, catechol, bisphenol A 
(4,4'-isopropylidenediphenol), bis(4,4'-dihydroxyphenyl)methane, 
2,2'-bis(4-hydroxyphenyl)pentane, 
3,3',5,5'-tetramethyl-4,4'-dihydroxydiphenyl, 4,4'-dihydroxydiphenyl 
sulfone, 4,4'-dihydroxybenzophenone, 
3,3',5,5'-tetrabromo-4,4'-isopropylidenediphenol, 
4,4'-bis(p-hydroxyphenyl)diphenyl ether, 4,4'-dihydroxydiphenyl suflide, 
mixtures thereof and the like. Most preferred as the bisphenol is 
bisphenol A. 
Suitable advancement catalysts which can be employed in the process of the 
present invention include most any catalyst which will catalyze the 
reaction between a vicinal epoxy group and a phenolic hydroxyl group. Such 
catalysts include, for example, those disclosed in U.S. Pat. Nos. 
3,306,872; 3,341,580; 3,379,684; 3,477,990; 3,547,881; 3,637,590; 
3,843,605; 3,944,855; 3,956,237; 4,048,141; 4,093,650; 4,131,633; 
4,132,706; 4,171,420; 4,177,216 which are incorporated herein by 
reference. 
Particularly suitable catalysts are the quaternary phosphonium and ammonium 
compounds such as, for example, ethyltriphenylphosphonium chloride, 
ethyltriphenylphosphonium bromide, ethyltriphenylphosphonium iodide, 
ethyltriphenylphosphonium acetate, ethyltriphenylphosphonium 
acetate.acetic acid complex, ethyltriphenylphosphonium phosphate, 
tetrabutylphosphonium chloride, tetrabutylphosphonium bromide, 
tetrabutylphosphonium iodide, tetrabutylphosphonium acetate, 
tetrabutylphosphonium acetate.acetic acid complex, 
butyltriphenylphosphonium tetrabromobisphenate, butyltriphenylphosphonium 
bisphenate, butyltriphenylphosphonium bicarbonate, benzyltrimethylammonium 
chloride, tetramethylammonium hydroxide, mixtures thereof and the like. 
After completion of either the copolymerization reaction (I) or the 
advancement reaction (II), it is generally beneficial, although not 
required, to subject the reaction product to a vacuum stripping step. This 
is accomplished by pulling a vacuum on the reactor, thus removing and 
condensing any materials which volatilize from the reaction product. 
In a variation on this vacuum stripping step, various modifying agents or 
additives, such as, for example, flow control agents, gloss control 
agents, pigments, texture control additives, air release agents, mixtures 
thereof and the like may added to the reaction product prior to the vacuum 
stripping step. This allows for removal of any volatile components 
contributed by said additives. 
Suitable carboxylic acid and/or hydroxyl functional polyesters which are 
combined with the advanced epoxy resgins are prepared using methods well 
known to the art. Typical of these methods and the polyesters resulting 
therefrom are those described in Kirk-Othmer Encyclopedia of Chemical 
Technology, Second Edition, Volume 16, Interscience Publishers, pp. 
159-189 (1968) and Encyclopedia of Polymer Science and Technology, Volume 
11, Interscience Publishers, pp. 62-128 (1969) which are incorporated 
herein by reference. 
Especially suitable polyesters include those prepared by reaction of 
neopentyl glycol and terephthalic acid; neopentyl glycol, terephthalic 
acid and trimethylolpropane; neopentyl glycol, terephthalic acid and 
trimellitic anhydride; neopentyl glycol, terephthalic acid and isophthalic 
acid; and neopentyl glycol, terephthalic acid and trimellitic anhydride. 
Formulating methods well known to the prior art are employed to prepare the 
powder coating formulations of the present invention. Preparation of 
typical epoxy resin based powder coating formulations are described in 
Fundamentals of Powder Coating by Miller and Taft, 1974, Society of 
Manufacturing Engineers, Dearborn, Michigan which is incorporated herein 
by reference. 
In the general method of preparation, the solid epoxy resin product is 
flaked or ground then dry mixed or blended with a non-sintering polyester 
and optionally, one or more accelerators or catalysts, particulate 
fillers, pigments, flow control agents, gloss control additives, texture 
control additives and air release agents. The dry mixed product is then 
hot melt blended typically by use of a kneading-type extruder. The 
extruded product passes through chilled rollers and is then recovered and 
crushed to a rough powder. Further grinding to a fine powder is 
accomplished via use of a high speed hammer mill or other type of grinding 
equipment. The resulting fine powder is subjected to a size classification 
step to recover the desired range of product particle size. The desired 
product size distribution for the product may vary depending on the 
intended end use of the product, but generally, sizes between about 80 
mesh to about 325 mesh are most desired. Well known methods that are 
suitable for use in size classifying powder coating formulatios include 
screening and air classification. 
The resulting powder coating formulation is applied to the substrate to be 
coated using methods well known to the prior art. These methods are 
delineated in detail by the aforementioned Miller and Taft reference and 
include powder dusting, fluidized bed processes, electrostatic powder 
spraying, electrostatic fluidized bed processes, and others. 
The powder coated article is cured using methods and conditions well known 
to the prior art. This typically involves heating in an oven for an amount 
of time sufficient to complete the cure. When used with the epoxy resin 
compositions of the present invention, curing times of about 5 minutes to 
about 30 minutes at a reaction temperature of from about 150 to about 
220.degree. C. are generally sufficient. 
The powder coating formulation optionally, contains one or more 
accelerators or catalysts. Suitable such accelerators or catalysts are 
described in the aforementioned Handbook of Epoxy Resins and Fundamentals 
of Powder Coating references. Representative of these accelerators or 
catalysts are the amino substituted pyridines, imidazoles, metallic salts, 
tertiary amines, phenols, mixtures thereof and the like. 
The powder coating formulation optionally, athough preferably, contains one 
or more particulate fillers. Fillers are used in powder coatings for a 
wide range of purposes, primary of which is economic, i.e. as a less 
expensive diluent. Other properties imparted by fillers cna include one or 
more of the following: handling and processing properties, impact 
modification, dimensional stability, moisture and chemical resistance, 
flame resistance, modified thermal conductivity, modified electrical 
properties, modified rheology, color modification and texture 
modification. Suitable such fillers are described in Non-Fibrous Fillers 
for Epoxy Resin Formulations presented at the 7th Electrical Insulation 
Conference, Chicago, Illinois. Oct. 15-19, 1967 by D.A. Shimp. 
Representative of these fillers are barytes (BaSO.sub.4), titanium 
dioxide. carbon black, silica flour, calcium carbonate, mixtures thereof 
and the like. The particle size distribution, shape, chemical composition, 
surface area and use level, i.e. resin to filler ratio, can be adjusted 
singularly or collectively to change the resultant cured powder coating. 
Simple preliminary experiments with the normal capability of those skilled 
in the art are ordinarily performed to aid in filler choice. 
The powder coating formulation optionally contains one or more pigments. 
Said pigments are typically used to add color to the cured powder coating. 
Suitable such pigments are described in Pigments for Colouring Epoxy 
Powder Coatings by Maltman and Deverell-Smith in Pigment and Resin 
Technology, November 1973, pp. 15-19 which is incorporated herein by 
reference. 
The powder coating formulation optionally, although preferably, contains 
one or more flow control agents. Flow control agents are used in powder 
coatings to adjust the rheological properties of the total powder coating 
formulation thus insuring uniform coating film thickness, wet-out and 
costing of edges. Suitable such flow control agents are described in 
Acrylic Flow Control Agents for the Coating Industry by Skora in Polymers 
Paint and Colour Journal, Sept. 5, 1979, pp. 867-870 which is incorporated 
herein by reference. Most preferred as the flow control agents are the 
polyacrylates such as, for example, ethyl acrylate and 2-ethylhexyl 
acrylate copolymer, and poly(butyl acrylate). 
The powder coating formulation optionally contains one or more texture 
control additives. Texture control additives are used in powder coatings 
to modify the surface characteristics of the cured powder coating. 
Materials which provide smooth or rough surface finishes may be employed. 
Glass microspheres, metal powders and polymeric powders are examples of 
the types of additives capable of modifying the powder coating surface to 
a textured finished. 
The powder coating formulation optionally contains one or more air release 
agents. Said agents are used in powder coatings to alleviate surface 
defects, such as pinholes in the cured powder coating, induced by air 
entrainment. A most preferred air release agent is benzoin, as described 
in Surface Coatings, Vol. 2 - Paints and Their Application by The Oil and 
Colour Chemists' Association, Australia, published by Chapman and Hall, 
1984, p. 598 which is incorporated herein by reference. 
The powder coating formulation optionally contains one or more gloss 
control additives. Gloss control additives are used to reduce the high 
degree of reflected light from the typical cured epoxy resin surface. 
Suitable such gloss control agents are certain amorphous silicas, silicic 
acid and the like. 
Other additives or adjuvants may be incorporated into the powder coating 
formulations of the present invention for their known and intended use 
therein. One such additive is a slip aid, as described in the 
aforementioned Surface Coatings article. 
The cured product of the present invention is a powder coating over a 
substrate such as steel which provides excellent aqueous corrosion 
resistance with high mechanical strength. 
The following examples are illustrative of the present invention and are 
not to be construed as to limiting the scope thereof in any manner.

EXAMPLE 1 
A. Preparation of Polystyrene Modified Advanced Epoxy Resin 
A low gloss polystyrene modified advanced epoxy resin was prepared in a 10 
gallon, stainless steel Pfaudler reactor. The reactor was equipped with 
mechanical stirring, nitrogen supply and pressure/vacuum control with a 
range of 1 to 50 psia (6.9-344.7 kPa). Temperature control was provided by 
a dual hot and cool heat transfer fluid system circulating through the 
reactor jacket. All reactants were preweighed prior to charging to the 
reactor. A 2-inch (50.8 mm) handway fitted on the top section of the 
reactor was used to charge all reactants to the reactor with the exception 
of the monomer solution and the TBPB. The monomer solution and the TBPB 
were charged to auxiliary feed vessels from which they were metered into 
the reactor at a controlled rate during the monomer solution addition 
step. The TBPB flow rate control was automatically linked to the monomer 
solution flow rate in such a way that the ratio of their addition rates 
remained constant throughout the monomer solution addition step. The 
vacuum system was equipped with a chilled water condenser and a knockout 
pot to recover any unreacted monomer and other lights during the vacuum 
strip step. A nitrogen vapor phase was provided by repetitively reducing 
the pressure to 10 psia (68.9 kPa) and pressuring the reactor to 24 psia 
(165.5 kPa) with nitrogen during the degassing steps. The product was 
transferred via a drumming line from the bottom tap of the reactor through 
a 50 micron sock filter and into the product drums during the drumming 
step. 
The following reactants and amounts were utilized: 
______________________________________ 
D.E.R. .RTM. 383 diglycidyl ether of 
15,857 grams 
bisphenol A having an EEW of 180.5 
commercially available from The Dow 
Chemical Company 
glacial methacrylic acid 
75.7 grams 
tertiary butyl perbenzoate (TBPB) 
317 grams 
bisphenol A 4,309 grams 
advancement catalyst.sup.1 
26.5 grams 
monomer solution 12,796 grams 
______________________________________ 
.sup.1 ethyltriphenylphosphonium acetate.acetic acid complex 70% in 
methanol 
The monomer solution was a mixture of the following reactants in the 
indicated amounts: 
______________________________________ 
styrene 12,682 grams 
glacial methacrylic acid 
114 grams 
______________________________________ 
The following reaction order and conditions were used: 
______________________________________ 
Reactor 
Temper- Reactor Cumulative 
Reaction Step ature Pressure Time 
______________________________________ 
Charge liquid ambient 14.7 psia 0 min. 
D.E.R. .RTM. 383 and (101.4 kPa) 
methacrylic acid 
Close reactor, pad 
-- 23.5 psia 10 min. 
with nitrogen and (162 kPa) (600 s) 
start agitation 
Heat reactor with 
-- 23.5 psia 15 min. 
155.degree. C. hot heat (162 kPa) (900 s) 
transfer fluid 
Charge monomer and 
-- 23.5 psia 15 min. 
TBPB to respective (162 kPa) (900 s) 
feed vessels 
Degas reactor three 
137.degree. C. 
-- 46 min. 
times (2760 s) 
Start monomer solu- 
146.degree. C. 
15.8 psia 1 hr. 8 min. 
tion and TBPB feed (108.9 kPa) 
(4080 s) 
Reactor temperature 
150.degree. C. 
16.4 psia l hr. 8 min. 
controlled at 150 .+-. 5.degree. C. 
(113.1 kPa) 
(4080 s) 
Monomer solution and 
150.degree. C. 
17.2 psia 2 hr. 52 min. 
TBPB feed complete (118.6 kPa) 
(10320 s) 
Start vacuum strip by 
152.degree. C. 
-- 3 hr. 39 min. 
slow reduction in (13140 s) 
pressure 
Vacuum strip at 
150.degree. C. 
0.2 psia 4 hr. 9 min. 
minimum pressure (1.4 kPa) (14940 s) 
Vacuum strip 150.degree. C. 
0.3 psia 4 hr. 19 min. 
complete (2.1 kPa) (15540 s) 
Bisphenol A charged 
153.degree. C. 
14.7 psia 4 hr. 28 min. 
to reactor (101.4 kPa) 
(16080 s) 
Advancement catalyst 
147.degree. C. 
10.0 psia 4 hr. 39 min. 
charged to reactor (68.9 kPa) 
(16740 s) 
Reactor degassed 
-- -- 4 hr. 45 min. 
4 times (17100 s) 
Reactor heated with 
152.degree. C. 
17.4 psia 4 hr. 51 min. 
190.degree.-200.degree. C. hot heat 
(120.0 kPa) 
(17460 s) 
transfer fluid 
Maximum temperature 
188.degree. C. 
18.1 psia 5 hr. 32 min. 
reached and slow (124.8 kPa) 
(19920 s) 
cooling started 
Reactor temperature 
175.degree. C. 
18.5 psia 6 hr. 2 min. 
controlled at 175 .+-. 5.degree. C. 
(127.6 kPa) 
(21720 s) 
Product drummed through 
175.degree. C. 
-- 6 hr. 42 min. 
50 micron sock filter (24120 s) 
into product drums 
______________________________________ 
B. Preparation of Polystyrene Modified Advanced Epoxy Resin (30 pbw) and 
Polyester (70 pbw) Copolymer (Filled) 
A portion of polystyrene modified advanced epoxy resin from A above (95.7 
grams, 0.1434 equivalent) having an epoxide equivalent weight (EEW) of 
667.4, a commercially available carboxylic acid functional polyester 
(229.54 grams, 0.1434 equivalent) (Uralac P2450, DSM Resins) having an 
average equivalent weight of 1600, titanium dioxide (162.59 grams, 0.5:1 
filler to binder ratio) (Dupont R-900), benzoin (2.5 grams) (Uraflow B, 
Scado) and a polyacrylate flow control agent (9.76 grams) (Modaflow II, 
Monsanto) were placed in a plastic bag, sealed and dry mixed to a 
homogeneous dry blend. The dry-mixed formulation was then extruded in a 
Buss-Condux PLK 45 single screw extruder (equipped with a 46 mm diameter 
kneader screw operated at 120 rpm) with Zone 1 at 50.degree. C. and Zone 2 
at 100.degree. C. The extrudate was passed through BCI Chill Rolls (61/2", 
165.1 mm, diameter), cooled and crushed. The crushed extrudate was then 
fine ground in a Brinkmann Centrifugal Grinding Mill utilizing the 
24-tooth grinding attachment. The finely ground extrudate was sieved 
through No. 140 (150 mesh, 100 .mu.m) standard test sieves (wire cloth). 
Portions of the -150 mesh powder coating formulation were applied via 
electrostatic spray with a Gema Ag Type 710 Laboratory Uit (set at 60-70 
kV) on the 4".times.12".times.20 gauge (101.6 mm.times.304.8 
mm.times.0.529 mm) cold rolled steel, clean treatment Parker test panels 
(Parker Division, Hooker Chemicals and Plastics Corporation). The 
electrtostatically coated panels were set in a Blue M Touchmatic 
convection-type oven (Model No. POM7) and cured at 180.degree. C. 
(356.degree. F.) for twenty minutes (1200 s). After removal from the oven 
the panels were cooled and evaluated via the following test methods: 
coating thickness was determined per ASTM D1186 by utilizing a Fischer 
Perma-Scope ES film thickness tester. Surface gloss was determined per 
ASTM D523 (DIN 67530) using a Mallinckrodt Multi Gloss gloss meter. 
Yellowness index of the surface was determined per FTMS141b Method 6131 
using a Gardner XL 10 CDM Tristimulus Colorimeter. Gardner forward and 
reverse impact strengths were determined per ASTM D2794 using a Gardner 
"Coverall" Bend and Impact Tester, 46 inch (1.17 m) tube length, 0-160 
in.-lb. tester, with a four pound (1.81 kg), one-half inch (12.7 mm) 
diameter cone. Visualization of any surface cracks at the impact sites was 
facilitated by application of an acidified copper sulfate (CuSO.sub.4) 
solution for a period of 15 minutes (900 s). Impact areas were observed 
for copper deposits or iron-rust stains after exposure to the copper 
sulfate solution. 
A portion of the -150 mesh powder coating formulation was evaluated for 
stroke cure gel time on a hot plate maintained at 180.degree. 
C..+-.1.degree. C. by stroking the one gram sample back and forth with a 
spatula until no fibers of resin adhered to the spatula when pulled up. 
The results of these tests are reported in Table I. 
EXAMPLE 2 
Preparation of Polystyrene Modified Advanced Epoxy Resin (30 pbw) and 
Polyester (70 pbw) Copolymer (Unfilled) 
A portion of polystyrene modified advanced epoxy resin from Example 1-A 
(143.57 grams, 0.2151 equivalent), a commercially available carboxylic 
acid functional polyester (344.17 grams, 0.2151 equivalent) (Uralac P2450, 
DSM Resins), benzoin (2.5 grams) and a polyacrylate flow control agent 
(9.76 grams) were placed in a plastic bag, sealed and dry mixed to provide 
a homogeneous dry blend which was further processed and evaluated using 
the method of Example 1-B. The results are reported in Table I. 
EXAMPLE 3 
Preparation of Polystyrene Modified Advanced Epoxy Resin (35 pbw) and 
Polyester (65 pbw) Copolymer (Filled) 
A portion of polystyrene modified advanced epoxy resin from Example 1-A 
(121.41 grams, 0.1819 equivalent), a commercially available carboxylic 
acid functional polyester (203.74 grms, 0.1819 equivalent) (Uralac P2610, 
DSM Resins) having an average equivalent weight of 1120, titanium dioxide 
(162.59 grams, 0.5:1 filler to binder ratio) (Dupont R-900), benzoin (2.5 
grams) (Uraflow B, Scado) and a polyacrylate flow control agent (9.76 
grams) (Modaflow II, Monsanto) were placed in a plastic bag, sealed and 
dry mixed to provide a homogeneous dry blend which was further processed 
and evaluated using the method of Example 1-B. The results are reported in 
Table I. 
EXAMPLE 4 
Preparation of Polystyrene Modified Advanced Epoxy Resin (35 pbw) and 
Polyester (65 pbw) Copolymer (Unfilled) 
A portion of polystyrene modified advanced epoxy resin from Example 1-A 
(182.12 grams, 0.2729 equivalent), a commercially available carboxylic 
acid functional polyester (305.62 grams, 0.2729 equivalent) (Uralac P2610, 
DSM Resins), benzoin (2.5 grams) and a polyacrylate flow control agent 
(9.76 grams) were placed in a plastic bag, sealed and dry mixed to provide 
a homogeneous dry blend which was further processed and evaluated using 
the method of Example 1-B. The results are reported in Table I. 
EXAMPLE 5 
Preparation of Polystyrene Modified Advanced Epoxy Resin (50 pbw) and 
Polyester (50 pbw) Copolymer (Filled) 
A portion of polystyrene modified advanced epoxy resin from Example 1-A 
(158.70 grams, 0.2378 equivalent), a commercially available carboxylic 
acid functional polyester (166.45 grams, 0.2378 equivalent) (Uralac P2980, 
DSM Resins) having an average equivalent weight of 750, titanium dioxide 
(162.58 grams, 0.5:1 filler to binder ratio) (Dupont R-900), benzoin (2.5 
grams) (Uraflow B, Scado) and a polyacrylate flow control agent (9.76 
grams) (Modaflow II, Monsanto) were placed in a plastic bag, sealed and 
dry mixed to provide a homogeneous dry blend which was further processed 
and evaluated using the method of Example 1-B. The results are reported in 
Table I. 
EXAMPLE 6 
Preparation of Polystrene Modified Advanced Epoxy Resin (50 pbw) and 
Polyester (50 pbw) Copolymer (Unfilled) 
A portion of polystyrene modified advanced epoxy resin from Example 1-A 
(238.06 grams, 0.3567 equivalent), a commercially available carboxylic 
acid functional polyester (249.69 grams, 0.3567 equivalent) (Uralac P2980, 
DSM Resins), benzoin (2.5 grams) and a polyacrylate flow control agent 
(9.76 grams) were placed in a plastic bag, sealed and dry mixed to provide 
a homogeneous dry blend which was further processed and evaluated using 
the method of Example 1-B. The results are reported in Table I. 
COMATIVE EXPERIMENT A 
Preparation of Advanced Epoxy Resin (35 pbw) and Polyester (65 pbw) 
Copolymer Standard (Filled) 
A portion of a commercial grade of a bisphenol A advanced diglycidyl ether 
of bisphenol A (127.85 grams, 0.1761 equivalent) (DER 662UH, Dow Chemical 
Company) having an EEW of 726, a commercially available carboxylic acid 
functional polyester (197.27 grams, 0.1761 equivalent) (Uralac P2610, DSM 
Resins) having an average equivalent weight of 1120, titanium dioxide 
(162.59 grams, 0.5:1 filler to binder ratio) (Dupont R-900), benzoin, (2.5 
grams) (Uraflow B, Scado) and a polyacrylate flow control agent (9.76 
grams) (Modaflow II, Monsanto) were placed in a plastic bag, sealed and 
dry mixed to provide a homogeneous dry blend which was further processed 
and evaluated using the method of Example 1-B. The results are reported in 
Table I. 
COMATIVE EXPERIMENT B 
Preparation of Advanced Epoxy Resin (35 pbw) and Polyester (65 pbw) 
Copolymer Standard (Unfilled) 
A portion of a commercial grade of a bisphenol A advanced diglycidyl ether 
of bisphenol A (191.82 grams, 0.2642 equivalent) (DER 662UH, Dow Chemical 
Company) a commercially available carboxylic acid functional polyester 
(295.92 grams, 0.2642 equivalent) (Uralac P2610, DSM Resins), benzoin (2.5 
grams) (Uraflow B, Scado) and a polyacrylate flow control agent (9.76 
grams) (Modaflow II, Monsanto) were placed in a plastic bag, sealed and 
dry mixed to provide a homogeneous dry blend which was further processed 
and evaluated using the method of Example 1-B. The results are reported in 
Table I. 
COMATIVE EXPERIMENT C 
Preparation of Advanced Epoxy Resin (30 pbw) and Polyester (70 pbw) 
Copolymer Standard (Filled) 
A portion of a commercial grade of a bisphenol A advanced diglycidyl ether 
of bisphenol A (101.49 grams, 0.1398 equivalent) (DER 662UH, Dow Chemical 
Company) having an EEW of 726, a commercially available carboxylic acid 
functional polyester (223.68 grams, 0.1398 equivalent) (Uralac P2450, DSM 
Resins) having an average equivalent weight of 1600, titanium dioxide 
(162.50 grams, 0.5:1 filler to binder ratio) (Dupont R-900), benzoin (2.5 
grams) (Uraflow B, Scado) and a polyacrylate flow control agent (9.76 
grams) (Modaflow II, Monsanto) were placed in a plastic bag, sealed and 
dry mixed to provide a homogeneous dry blend which was further processed 
and evaluated using the method of Example 1-B. The results are reported in 
Table I. 
COMATIVE EXPERIMENT D 
Preparation of Advanced Epoxy Resin (30 pbw) and Polyester (70 pbw) 
Copolymer Standard (Unfilled) 
A portion of a commercial grade of a bisphenol A advanced diglycidyl ether 
of bisphenol A (152.23 grams, 0.2097 equivalent) (DER 662UH, Dow Chemical 
Company) a commerically available carboxylic acid functional polyester 
(335.51 grams, 0.2097 equivalent) (Uralac P2450, DSM Resins), benzoin (2.5 
grams) (Uraflow B, Scado) and a polyacrylate flow control agent (9.76 
grams) (Modaflow II, Monsanto) were placed in a plastic bag, sealed and 
dry mixed to provide a homogeneous dry blend which was further processed 
and evaluated using the method of Example 1-B. The results are reported in 
Table I. 
COMATIVE EXPERIMENT E 
Preparation of Advanced Epoxy Resin Standard Powder Coating (Filled) 
A portion of a commercial grade of a bisphenol A advanced diglycidyl ether 
of bisphenol A (400.0 grams, 0.5510 equivalent) (DER 662UH, Dow Chemical 
Company) having an EEW of 726, dicyandiamide (7.59 grams), 83 percent by 
weight dicyandiamide and 17 percent by weight 2-methylimidazole mixture 
(4.8 grams), titanium dioxide (200 grams, 0.5:1 filler to binder ratio) 
(Dupont R-900), benzoin (3.12 grams) (Uraflow B), and a polyacrylate flow 
control agent (12.0 grams) (Modaflow II, Monsanto) were placed in a 
plastic bag, sealed and dry mixed to provide a homogeneous dry blend which 
was further processed and evaluated using the method of Example 1-B. The 
results are reported in Table I. 
COMATIVE EXPERIMENT F 
Preparation of Advanced Epoxy Resin Standard Powder Coating (Unfilled) 
A portion of a commercial grade of a bisphenol A advanced diglycidyl ether 
of bisphenol A (550.0 grams, 0.7576 equivalent) (DER 662UH, Dow Chemical 
Company) having an EEW of 726, dicyandiamide (10.43 grams), 83 percent by 
weight dicyandiamide and 17 percent by weight 2-methylimidazole mixture 
(6.6 grams), benzoin (2.89 grams) (Uraflow B), and a polyacrylate flow 
control agent (11.0 grams) (Modaflow II, Monsanto) were placed in the 
plastic bag, sealed and dry mixed to provide a homogeneous dry blend which 
was further processed and evaluated using the method of Example 1-B. The 
results are reported in Table I. 
TABLE I 
__________________________________________________________________________ 
Designation 
Film Gloss 
Gardner Impact 
Stroke Cure 
of Thickness 
Degrees/ 
Forward/Reverse 
Gel Time @ 180.degree. C. 
Yellowness 
Coating 
Formulation 
mils (mm) 
Percent 
in-lb (J) 
(sec) Index Appearance.sup.1 
__________________________________________________________________________ 
Example 1 
1.7 20/29.6 
160/160 316.1 -0.1-+1.6 
flawless 
(0.043) 
60/73.6 
(18/18) 
85/76.5 
Example 2 
1.14 20/58.6 
160/160 276.7 -- flawless 
(0.029) 
60/108.8 
(18/18) 
85/89.3 
Example 3 
1.6 20/48.2 
160/160 216.4 -0.4-+0.2 
2 
(0.041) 
60/88.5 
(18/18) 
85/91.5 
Example 4 
1.2 20/81.4 
160/160 185.0 -- 2 
(0.025) 
60/118.3 
(18/18) 
85/96.2 
Example 5 
1.4 20/38.7 
160/160 132.3 -1.4--0.4 
2 
(0.036) 
60/81.6 
(18/18) 
85/83.7 
Example 6 
1.13 20/54.8 
160/160 96.6 -- 2 
(0.029) 
60/96.8 
(18/18) 
85/92.2 
Comp. Expt. A 
1.7 20/76.6 
160/160 272.4 +0.4-0.7 
1 
(0.043) 
60/92.7 
(18/18) 
85/96.5 
Comp. Expt. B 
1.7 20/111.3 
160/160 195.7 -- 1 
(0.043) 
60/131.8 
(18/18) 
85/97.9 
Comp. Expt. C 
1.56 20/30.4 
160/160 326.5 0.0-+0.7 
2 
(0.040) 
60/74.6 
(18/18) 
85/75.3 
Comp. Expt. D 
1.17 20/62.3 
160/160 278.2 -- 2 
(0.030) 
60/112.4 
(18/18) 
85/88.6 
Comp. Expt. E 
1.6 20/24.1 
160/160 383.6 +0.9-1.6 
2 
(0.041) 
60/69.2 
(18/18) 
85/71.2 
Comp. Expt. F 
1.3 20/95.6 
160/160 246.1 -- 1 
(0.033) 
60/123.7 
(18/18) 
85/95.9 
__________________________________________________________________________ 
.sup.1 1 = slight to barely perceptible textured surface 2 = pronounced 
textured surface (orange peel) 
EXAMPLE 7 
Portions of the powder coating formulations of Example 4, Comparative 
Experiment B and Comparative Experiment F (6.50 grams) were placed in 
2-inch diameter circular aluminum dishes then cured in an oven for 30 
minutes (1800 s) at 180.degree. C. The resulting circular clear unfilled 
castings were demolded and weighed after removal from the oven. A casting 
from each respective cured resin was added to a glass jar containing 
deionized water, 1 percent by weight aqueous sodium hydroxide and 1 normal 
hydrochloric acid. The jars were then maintained in an oven at 92.degree. 
C. and the samples were removed and weighed at the indicated intervals. 
The results are reported in Table II. 
TABLE II 
______________________________________ 
Percent Weight Gain 
Example Comp. Comp. 
4 Expt. B Expt. F 
______________________________________ 
Hours of Exposure to 
92.degree. C. Deionized Water 
24 1.84 2.31 3.12 
41 2.03 2.55 4.40 
72 2.36 2.87 5.17 
Hours of Exposure 
to 92.degree. C. Aqueous 
NaOH (1 pbw) 
24 0.81 1.73 2.94 
41 2.88 1.76 5.26 
72 .sup. 1.35.sup.1 
.sup. 1.27.sup.1 
.sup. 4.68.sup.1 
Hours of Exposure to 
92.degree. C. Aqueous HCl (1N) 
24 1.42 1.61 3.87 
41 1.42 1.95 .sup. 5.59.sup.2 
72 1.46 .sup. 1.84.sup.2 
.sup. 6.67.sup.2 
______________________________________ 
.sup.1 surface chalking 
.sup.2 surface pitting