Chemistry and Technology of Acrylic Resins for Coatings - American

42

Chemistry and Technology of Acrylic Resins for Coatings

Downloaded by NORTH CAROLINA STATE UNIV on January 15, 2013 | http://pubs.acs.org Publication Date: September 25, 1985 | doi: 10.1021/bk-1985-0285.ch042

W. H. BRENDLEY and R. D. BAKULE Rohm and Haas Company, Spring House, PA 19477 History of the Synthesis of Acrylic Monomers and Polymers Relation between the Properties and Composition of Acrylic Coating Polymers General Resistance and Durability Properties Development of Thermoplastic Acrylic Coatings Development of Thermosetting Acrylic Coatings Recent Trends in Acrylic Coatings Approaches to Low-Emission Acrylic Coatings Aqueous Thermoplastic Emulsions Aqueous Thermosetting Emulsions Water-Reducible Polymers Solubilizable Dispersions High-Solids Coatings Oligomers/Poligomers Powder Coatings Radiation-Cured Coatings

For the past 50 years, protective and decorative coatings based on acrylic and methacrylic polymers have found increasing use in a variety of industrial and trade sale applications. This expanded usage has occurred because of the versatile and unique properties of these polymers and because of the development of large-scale commercial processes for a variety of monomers. This paper reviews the history of the development of thermoplastic and thermosetting acrylic polymers, relates their chemical and physical properties to the unique virtues they possess as coatings, and looks into the future of acrylics in coatings. Several examples of the application of acrylic technology to specific market segments—automotive and appliance finishes—illustrate how acrylic polymers can be tailored to meet specific end use requirements. 0097-6156/ 85/ 0285-1031 $06.50/0 © 1985 American Chemical Society

In Applied Polymer Science; Tess, R., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1985.

1032

APPLIED POLYMER SCIENCE

History of the Synthesis of Acrylic Monomers and Polymers (1-4) Although acrylic acid was first synthesized in 1843 and polymerized in 1847, the properties of derived monomers and polymers were not extensively investigated until the classic work of Otto Rohm, beginning in 1901. The first general synthetic process for manufacturing acrylic esters was accomplished in 1927 in Germany and was based on the reactions A. CH=CH + HC10 Downloaded by NORTH CAROLINA STATE UNIV on January 15, 2013 | http://pubs.acs.org Publication Date: September 25, 1985 | doi: 10.1021/bk-1985-0285.ch042

2

> C1HCCH0H

2

2

C1HCCH0H + NaCN 2

> NCCHCH0H + NaCl

2

2

NC-CHCH-0H + ROH + 0.5H S0A 2

2

2

2

> CH =CH-CCLR + ^0.5(NH^) S0

2

9

2

4

developed by Rohm and his associate Otto Haas. Before the development was completed, however, Haas had immigrated to the United States, where he developed the first commercial production of methyl and ethyl acrylate in the United States in the early 1930s using the ethylene-cyanide process. Processes for a variety of acrylic monomers were developed in the ensuing decades by Rohm and Haas and other manufacturers. Process 0 I! B. CH3CCH3 + HCN

Manufacturer

OH I > CH3C-CH3

Rohm and Haas Co. (1933)

OH (CH } C + H 0 + ROH + 0.5HS04 3

2

2

>

2

CN OH I (CH ) -C-C0 R + 0.5(NH ) S0 OH CH3 I P2O5 I (CH ) -C-C0 R, > CH=C-C0R + H 0 Ni(C0) C. HC=CH + ROH + CO > CH=CHC0R HC1 3 2

3 2

2

4 2

2

2

4

2

2

4

2

2

Rohm and Haas Co. (1948)


42.

Chemistry of Acrylic Resins for Coatings

BRENDLEY A N D BAKULE

OHD.

CH2-CH2 + HCN

Union Carbide (1949)

> H0CH2CH2CN

0 H O C H C H C N + ROH + H" 2

1033

>

2

CH =CHC0„R + NH.+ 2 2 4 o


NiX E.

HC=CH + CO + H20

F.

CH2=CHCN

H2S04

BASF (1956)

> CH2=CHC02H

> CH2=CH-CONH2

ROH H 2 S0 4

>

Ugilor

CH2=CH-C02R CH2C

0 G.

Celanese (1958)

CH2=C=0 + HCH CH 2 C A> CH2-C7

+ ROH

H 2 S0 4

> CH2=CHC02R

CH2 -0

CH3

CH3

I H.

/

CH3C-CN + H S 0 2

> CH2=C

4

OH

Rohm and Haas Co. ^:CNH2-H S0 2

4

Du Pont

0 CH3

1

CH2=C

J3NH2~H S0

(Γ

I.

2

+ ROH 4

CH2=CHCH3 + 302 2

H+

CH3

1

> CH2=C

j£0R

+ NH HS0

0>

> CH2=CHC02H + H20

4

4

Imperial

Chemical

Industries

Union Carbide (1969)


1034

A P P L I E D P O L Y M E R SCIENCE

CH3 I CH2=C-CH3


CH3 I CH2-C-CH0

Mo-Bi-Fe-Li [0]

CH2-C

CH3 / \

Nippon Geon (1975)

CHO

CH3 M0 1 2 P 2 VCs 2 Sr 0 5 S — CH2=C-C02H [0]

In addition to these primary methods for synthesizing a c r y l i c monomers, many other esters and functional monomers are prepared by further reactions of these monomers. Two common methods for obtaining new monomers are the following. K.

Direct esterification of the acid:

CH2=C

/

Rl

Rl / > CH2=C

+ R20H

+ H20

\o2R2

^C0 n 2

(where R = H or CH and R i s a l k y l ) ]

L.

3

2

Transesterification of the lower esters: Ri

CH2=C \

Ri

+ R30H C02R2

> CH2=C \

+ R20H C02R3

(where Rj = H or CH 3 and R 2 and R 3 are a l k y l functional groups)

or other

Further details on the preparation of acrylic monomers can be found in References 1, 2, 5, and 6. The essential point i s that an extremely wide variety of monomers are a v a i l a b l e on a commercial scale. This variety permits the acrylic polymer chemist an unusual freedom i n designing a polymer to meet a set of end use requirements. Relation Between the Properties and Composition of Acrylic Coating Polymers General. The solution and film properties of an acrylic coatings polymer are determined by (1) the molecular weight, (2) the nature of the polymer solution, and (3) the composition of the polymer backbone. The effect of molecular weight i s easy to v i s u a l i z e . Film formation in any solution coating depends either upon the formation



42.



1035

of primary chemical bonds (thermosetting coatings) or upon entanglement of the polymer chains by secondary chemical interactions (thermoplastic coatings). In the case of thermoplastic coatings, i t is evident that the longer the chains (i.e., the higher the molecular weight) the more thoroughly the chains w i l l be entangled and the more coherent the film w i l l be. As a result, the coating f i l m w i l l be tougher and more resistant to degradation. There is, however, a practical limit. After the molecular weight of the polymer reaches a value of about 90,000, l i t t l e improvement in properties accrues with increasing molecular weight. On the other hand, the viscosity of the coatings solution increases expotentially with the molecular weight (8). In ( η ρ / η 3 ) * KMaC where r|p and η 3 are the v i s c o s i t i e s of the polymer solution and solvent, respectively, M equals the molecular weight, C equals the polymer concentration, Κ equals a constant, and a equals a constant in the range of 0.5-1.5. Because of this sensitive dependence, a balance must be struck between the desirability of high molecular weight and the need to maintain a tractable viscosity at a reasonable applications solids. These considerations do not apply to emulsion coatings, which are dispersions of discrete polymer particles suspended in an aqueous continuum and whose viscosity is determined essentially by the continuum phase. A c r y l i c polymers used in coatings are composed primarily of polymethacrylates and polyacrylates: CH3

I

Η

I

{CH2-C}n

fCH 2 -Ç> n

C=0

C=0

1

i

0

0

1

R Polyraethacrylate

I

R Polyacrylate

and their properties are strongly influenced by three factors: (A) the presence of CH3 or H on the α - c a r b o n , (B) the length of the ester side chain, R, and (C) the presence of functionality in the ester side chain. (A) The presence of a methyl group in the α-position results in a hinderance to the segmental rotation of the polymer backbone. As a result, polymethacrylates are invariably harder, less extensive polymers than the corresponding acrylates (7) (Table I). (B) Similarly, as the length of the ester side chain increases, segmental rotations in the side chain, as well as an increase in the specific volume of the polymers, result in freer segmental motion within the polymer chain, with a concomitant decrease in t e n s i l e strength and an increase in the extensibility of the polymers (Table I). When one considers that commercial acrylic polymers are almost



1036

A P P L I E D POLYMER SCIENCE

always copolymers of several monomers, i t i s obvious that a wide range of strength and f l e x i b i l i t y can be achieved. (C) It i s well-known that the presence of certain types of functionality in the ester side chain imparts specific charac teristic film properties to the acrylic coating (7). Some of these characteristics are summarized in Table II. By knowing the end use requirements of f l e x i b i l i t y , adhesion, hardness, etc., the acrylic coatings polymer chemist can often tailor-make a polymer to f i t the defined needs of the application. The understanding of the relation between the macroscopic film properties of an a c r y l i c coating and the polymer composition has been advanced s i g n i f i c a n t l y by the successful application and interpretation of two physical models: (1) the glass transition temperature, T g ; (2) the solubility parameter, δ. The glass transition temperature, Tg, or more precisely the temperature range, is the temperature at which significant segmental rotation in the backbone and/or side chain is thermally excited. As the temperature of the coating increases and passes through this region, the properties of the polymer f i l m change dramatically. Below the Tg the film is relatively glassy, rigid, and hard. Above the Tg the film becomes more rubbery, flexible, and softer, because the polymer segments can respond to stresses impressed on them. Because the same molecular process, thermal excitation of segmental motion of the polymer chains, determines both the glass transition temperature and the tensile strength and extensibility of the polymer, i t i s not surprising to find a close correlation between the T e and these mechanical properties of polymers (Table 8 D. Burrell (9) has given an excellent exposition of the application of glass transition temperatures to coatings. One example w i l l i l l u s t r a t e how this concept unifies the interpretation of the performance of various types of coatings films. In Figure 1, the temperature dependence of the hardness of several thermoplastic and thermosetting films i s represented schematically. The polymer having T g < 25 °C is relatively soft and flexible at ambient conditions, whereas the polymer having Tg > 25 °C tends to be hard and brittle. The introduction of cross-linking w i l l have a minimal effect on hardness at temperatures less than Tg since segmental motion does not occur to any great extent. On the other hand, at temperatures above Tg, cross-linking s i g n i f i c a n t l y increases the f i l m hardness. By understanding the factors influencing the Tg of an a c r y l i c polymer, one can correlate and predict a variety of properties of actual coating systems (10-12). The solubility parameter concept invented by Hildebrand (13) and applied to polymers by Burrell (14) has also proved invaluable in understanding, correlating, and predicting the s o l u b i l i t y and compatibility of acrylic polymers. The solubility parameter, 6, is a consequence of regular solution theory, which assumes that the entropy of mixing the components of a solution i s the same as that for an ideal solution, for example, mixing is random, and that the enthalpy (heat) of mixing can be calculated from the model by making simplifying assumptions about the nature of the molecular interactions involved. The theory predicts that a polymer w i l l be miscible with another polymer, or solvent, i f the enthalpy of mixing


42.

B R E N D L E Y A N D B A K U LE

Table I.

1037

Properties of Polymethacrylates and Polyacrylates Tensile Strength (psi)

Compound Downloaded by NORTH CAROLINA STATE UNIV on January 15, 2013 | http://pubs.acs.org Publication Date: September 25, 1985 | doi: 10.1021/bk-1985-0285.ch042


Elongation (%)

Polyraethacrylate Methyl Ethyl Isobutyl n-Butyl

9000 5000 3500 1000

4 7 5 250

Polyacrylate Methyl Ethyl n-Butyl

1000 33 3

750 1800 2000

Table II.

Tg (°C)

105 65 48 20 9 -22 -54

Effect of Various Monomers on Film Properties

Film Property

Contributing Monomers

Exterior durability

Methyacrylates and acrylates

Hardness

Methyl methacrylate; styrene; methacrylic and acrylic acid

Flexibility

Ethyl acrylate; butyl acrylate; 2-ethylhexyl acrylate

Stain resistance

Short-chain methacrylates

Water resistance

Methyl methacrylate; styrene; long-chain methacrylates and acrylates

Mar resistance

Methacrylamide; acrylonitrile

Solvent and grease resistance

Acrylonitrile; methacrylamide; methacrylic acid

Adhesion to metals

Methacrylic/acrylic acid



1038


of the two materials i s e s s e n t i a l l y zero. This condition i s guaranteed i f the solubility parameters of the components are equal. Thus, polymers and solvents having similar solubility parameters are miscible. The practical consequence of this can be illustrated by using the data in Tables III and IV. Polymers containing long alkyl side chains are likely to have good resistance to water and alcohol since the solubility parameters of the polymer and solvents are quite different. Conversely, polar polymers, such as p o l y a c r y l o n i t r i l e , are predicted to show good resistance to attack by aliphatic hydrocarbons. By the same token, the longer alkyl chain acrylics are expected to be more soluble in aliphatic solvents since solubility parameter of the former polymers is more nearly equal to that of aliphatic hydrocarbons. These and related predictions of this theory have been experimentally verified innumerable times by coating chemists and formulators. Resistance and Durability Properties. A c r y l i c s generally have excellent durability properties. They r e s i s t discoloration when exposed to elevated temperatures and are not easily attacked by acids or bases. The reasons for these properties are to be found in the chemical nature of the polymer backbone. In the f i r s t place, the main polymer backbone is comprised entirely of C-C single bonds that are r e l a t i v e l y inert and not susceptible to hydrolysis l i k e ester, ether, or amide linkages. Even though the ester side chains can be hydrolyzed, with difficulty, such attack does not result in scission of the polymer backbone, and so, the f i l m maintains i t s integrity. There are significant differences to be found in the d u r a b i l i t y of various a c r y l i c s (_7, 15). These differences are summarized in Table V. The general superiority of methacrylates over acrylates results because the free radical intermediate contributing to chain scission -(CH2-C-CO2R)- is more readily formed in acrylates than in methacrylates. The increasing d u r a b i l i t y of the acrylates with increasing ester chain length results from the greater f l e x i b i l i t y and hydrophobicity of the softer polymers. They more readily withstand dimensional changes in the substrate without cracking and are more water repellant. Similar considerations also apply to copolymers. Experimentally, i t is found that the exterior d u r a b i l i t y of certain copolymers p l a s t i c i z e d to have the same Tg (15) decreases in the order BMA - MMA > MMA/BA > MMA/EA in agreement with the trends shown in Table V. In emulsion coatings where film formation occurs by coalescence of the polymer particles, adequate film formation must take place i f d u r a b i l i t y i s to be obtained. A water-based coating applied in a hot, dry environment may show much poorer durability than the same coating applied in a warm, wet environment. By the same token, i f the environment is too cold (less than the T g of the polymer), poor f i l m formation also results (15). In addition to the chemical inertness cited above, acrylics show superior d u r a b i l i t y because the polymers are transparent in the spectral region between 3500 and 3000 A, which i s the most photochemically active region of the solar spectrum. Modification of a c r y l i c s with polymers or pigments that absorb in this region,



42.

BRENDLEY AND BAKULE

Figure 1.

Table III.

1039


Hardness-temperature relationships for varying T g and degree of cross-linking.

polymers of

Solubility Parameters of Solvents

Solvent

6

Solvent

δ

Mineral spirits

7.0

Xylene

9.0

Ether

7.4

Methyl ethyl ketone

9.3

Carbon tetrachloride

8.6

Ethanol

12.7

Toluene

8.9

Water

23.4



1040

A P P L I E D POLYMER SCIENCE

Table IV.

Values for Acrylic Homopolymers (Small's Method)

Polymer

δ

δ

Polymer

Poly(methyl methacrylate)

9.4

Poly(methyl acrylate)

9.7

Poly(ethyl methacrylate)

9.0

Poly(ethyl acrylate)

9.2

Poly(n-butyl methacrylate)

8.7

Poly(n-butyl acrylate)

8.7

Poly(acrylonitrile)

Table V.

General Durability Characteristics of Acrylic Homopolymers

Substituent Methyl Ethyl Isobutyl n-Butyl

Durability Characteristics Methacrylate Acrylate Very good Excellent Excellent Excellent

Poor Fair Good Excellent


12.5

42.

BRENDLEY AND BAKULE


for example, alkyds and T1O2, durability of the coating.

1041

invariably reduces the exterior


Development of Thermoplastic Acrylic Coatings Prior to the mid-1950s, a l l thermoplastic a c r y l i c s were c l a s s i c solution polymers prepared in suitable organic solvents. They were employed in a variety of applications, including general industrial finishes and appliance enamels and coatings for a variety of wooden, metallic, and plastic substrates. The history of the introduction of thermoplastic acrylics into automotive finishes serves to i l l u s t r a t e the general growth of a c r y l i c technology during the 1950s (16) and the a b i l i t y of these polymers to be modified to f i l l sophisticated requirements. Prior to 1955, nitrocellulose lacquer was the dominant finish on automobiles. These finishes dried quickly, had a good appearance, were easy to repair, but lacked d u r a b i l i t y . Rapid loss of gloss required frequent polishing, which eventually eroded the coating. In 1956 General Motors introduced a thermoplastic acrylic lacquer developed by Du Pont. Because the coating, based on poly(methyl methacrylate), showed excellent durability, high pigmentation was not required as was the case in n i c t r o c e l l u l o s e lacquers. As a result, new metallic and "glamour" finishes could be used that were not practical in the old finishes. The acrylics were not perfect, however. They were d e f i c i e n t i n adhesion and f l e x i b i l i t y . I n i t i a l l y , these deficiencies were obviated by the addition of p l a s t i c i z e r s and the use of special primers. Eventually, the adhesion deficiency was eliminated by the incorporation of special adhesion-promoting monomers into the backbone i t s e l f . Like the older nitrocellulose lacquers, these acrylic finishes had to be polished to achieve maximum gloss. This costly operation was eliminated by the development of new technology commonly referred to as "bake-sand-bake." In this technique the lacquer is applied and baked long enough to allow repair of imperfections by sanding and recoating and then the entire body is baked at a higher temperature. The combined e f f e c t of retained s o l v e n t and p l a s t i c i z e r s causes the f i n i s h to reflow, f i l l i n g in a l l sanding scratches and leaving a smooth, glossy f i n i s h that requires no further polishing. Because the new acrylic finishes required minimal polishing by the auto owner, the finishes were subject to water spotting. When water, or bird droppings, dried on the hood and trunk in the hot sun, permanent etches were l e f t on the f i n i s h . Incorporation of longer ester chain methacrylates into the polymer backbone resolved this problem by rendering the coating more hydrophobic and also imparted improved f l e x i b i l i t y without loss of hardness, when used in conjunction with special plasticizers. Development of Thermosetting Acrylic Coatings The oldest thermosetting vehicle used by man is porcelain enamel, which is an aqueous dispersion of s i l i c a , sand, and other components fused to produce a hard, ceramic finish. These high-quality finishes are s t i l l used extensively in bathtubs and household appliances such as range tops and hot water heaters where extreme



1042


heat and chemical resistance i s required. However, the expense, lack of f l e x i b i l i t y , poor adhesion except to a few substrates, and intense heat required to fuse the finish limit the use of porcelain to a few special applications. In the decade following World War II, increased consumer demand and the resultant introduction of high-speed automated assembly line production of consumer goods demanded new coatings that dried rapidly or could be applied prior to fabrication. During this period four major types of a c r y l i c thermosetting systems were developed (17). These systems had the common feature that certain functionality was incorporated into the pendant ester group on the a c r y l i c backbone that could be reached with other functionality forming primary chemical bonds. The first types of systems are compared in Table VI. Within a few years numerous chemical schemes for cross-linking acrylic polymers were developed (18) commercially. A few of these are illustrated in Table VII. In Table V I I I , the r e l a t i v e performance of s e v e r a l a c r y l i c thermosetting systems i s compared with that of the older alkyd melamine. The superior d u r a b i l i t y of a c r y l i c s (T/P and T/S) and good metallic pigment control led to the rapid replacement of alkyd/melamine in U.S. automotive finishes. In appliance coatings where toughness and chemical resistance are c r u c i a l , acid crosslinked epoxies replaced alkyd melamines and provided the added benefit of resistance to yellowing by the finish. There are strengths and weaknesses among the various a c r y l i c thermosetting systems. For example, acid epoxies and urethane c r o s s - l i n k e d systems produce no v o l a t i l e byproducts. Cure temperatures differ widely (see Table VIII). These and other factors determine the acceptability of a particular system for a given application and allow the user considerable latitude i n choosing an acrylic that best meets his requirements. In summary, there are several distinct advantages of acrylics in thermosetting vehicles: (1) the variety of functional monomers that can be incorporated into the polymer to enable reaction with several cross-linking agents and provide specific properties such as adhesion to diverse substrates, efficient pigment wetting, and controlled cross-link density; (2) the variety of nonfunctional monomers available for imparting a desirable balance of hardness, toughness, and resistance properties; (3) the excellent inherent d u r a b i l i t y of a c r y l i c s i n e x t e r i o r and c h e m i c a l l y harsh environments. From World War II u n t i l the mid-sixties, solvent-based thermosetting acrylics cross-linked with nitrogen resins, epoxies, urethanes, and other modifiers exhibited superior properties and in many cases became the standard "best state of the art coating in a variety of applications including automotive finishes, appliance finishes, c o i l coatings for exterior siding, can coatings, and metal decorating. Recent Trends in Acrylic Coatings Since the mid-1960s, extraneous forces have brought about the need for new technology in coatings. These extraneous forces resulted from a growing concern about the emission of organic solvents into the atmosphere and the levels of volatile emissions to which workers



42.



Table VI.

First Thermosetting Acrylic Resins

Acrylic Functionality

Coreactant Functionality

0

Reaction Products

0

Ί

0

Manufacturer

OH

M l

/ \ 'VwHC

N^COH

CH2 AAA/ C-0-CH 2 -CH~w

0

0

2w*C-NH-CH20H

>^CNHCH 2 NHC^ W

0

0

A/v C0C2H4-0H

II

/\

~vN

/ I

OH + RiR 2 C=0

Η C ' Rl

X

R2 0

II

ί -NH-CH 2 -CH -0H 2

+

2RNC0

> | -N-CH2-CH2-OC-NHR C-NHR

II

0


42. BRENDLEY AND BAKULE


By proper selection of the radicals Ri and R » the rate of the isocyanate-oxazolidine reaction can be made much faster than that of the hydrolysis reaction of the isocyanate alone. Poligomers f i l l the gap between oligomers and conventional solvent-based vehicles. With MW ^5 χ 10^-5 χ 10^, they can be applied at high enough application solids to meet many current emission standards. As a result of their fairly low molecular weight, they must ordinarily be cross-linked. In many applications they can be handled by conventional techniques. Downloaded by NORTH CAROLINA STATE UNIV on January 15, 2013 | http://pubs.acs.org Publication Date: September 25, 1985 | doi: 10.1021/bk-1985-0285.ch042

2

Powder Coatings. Powder coatings, as the name implies, are solid particles of thermoplastic or thermosetting polymers, with pigment already incorporated, that are deposited on the substrate by electrostatic spray and subsequently fused into a continuous film by heat. When perfected, such coatings offer significant advantages in that no solvents or liquid vehicle are required. On the other hand, at present, deposition efficiency is less than 100% and the usual requirement that a single production line be capable of handling more than one color makes collection and recycling of the effluent powder a difficult problem. This approach no doubt w i l l find a place in future industrial coating applications. It is ironic that these experimental powder coatings mimic the oldest thermosetting finish—porcelain enamels. Radiation-Cured Coatings. Ultraviolet-cured and electron beam cured coatings are presently being used in certain applications such as board coatings and printing inks. The basic chemistry of such systems involves the initiation of the cross-linking reaction by ultraviolet radiation or electron bombardment. The polymerization then proceeds rapidly to completion. The transparency of acrylics in the ultraviolet region makes them an ideal vehicle for this type of application. While these are potentially zero emission coatings, present systems contain monomers, oligomers, and photoinitiators, some of which present volatility and toxicity concerns. Other problems such as the volume change that occurs during the cross-linking reaction and the difficulty of obtaining penetration of the ultraviolet radiation through pigmented films are not entirely resolved. This latter problem is not experienced in electron beam curing, and consequently this approach will probably find wider application in industrial coatings, although capital equipment costs are higher. In summary, acrylic industrial coatings have been employed for almost half a century in applications where durability and resistance to the environment are paramount. Over the years, numerous chemical technologies have been developed to achieve specific properties. Because of their versatility and their inherent resistance properties, acrylic polymers have played a central role in the development of coating technology. The growth of new technologies for low-emission coatings has increased this role even more. Literature Cited 1. Luskin, L. S.; Myers, R. J. "Encyclopedia of Polymer Science and Technology"; Wiley: New York, 1964; Vol. 1, pp. 177-444. In Applied Polymer Science; Tess, R., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1985.

1051


1052

APPLIED POLYMER SCIENCE

2. Riddle, Ε. Η. "Monomeric Acrylic Esters"; Reinhold: New York, 1954. 3. Salkind, M.; Riddle, E. H.; Keefer, R. W. Ind. Eng. Chem. 1959, 51, 1232. Ibid., 1328. 4. Allyn, Gerould "Acrylic Resins"; Federation of Society for Paint Technology: Philadelphia, 1971; Federation Series on Coatings Technology, Vol. 17. 5. Sittig, M. "Acrylic Acid and Esters"; Noyes Development Corp.: Park Ridge, N.J., 1965. 6. Yokum, R. H. "Functional Monomers, Their Preparation, Polymerization, and Applications"; Dekker: New York, 1973; Vol. 1, 2. 7. Brendley, W. H. Paint Varnish Prod. 1973, 63, 19. 8. Mercurio, Α.; Lewis, S. N. J. Paint Technol. 1975, 47, 37. 9. Burrell, H. Off. Dig. 1962, 34(445), 131. 10. Akay, M.; Bryan, S. J.; White, E. F. T. J. Oil Colour Chem. Assoc. 1973, 56, 86. 11. Kelley, F. N.; Bueche, F. J. Polym. Sci. 1961, 50, 549. 12. Mercurio, A. Off. Dig. 1961, 987. 13. Hildebrand, J. L.; Prausnitz, John M.; Scott, R. L. "Regular and Related Solutions"; Van Nostrand-Reinhold: New York, 1970. 14. Burrell, H. Interchem. Rev. 1955, 14(1). 31. Burrell, H. J. Paint Technol. 1968, 40, 197. Burrell, H. Off. Dig. 1955, 27, 728. 15. Harren, R. E.; Mercurio, A. "Acrylic Coatings—Design for Maximum Weatherability"; Chicago Coatings Symposium, April 1974. 16. Beckwith, N. P. Paint Varnish Prod. 1973, 63, 15. 17. Gerhart, H. L. Off. Dig. 1961, 680. 18. Piggot, Κ. E. J. Oil Colour Chem. Assoc. 1963, 46, 1009. 19. Brendley, W. H.; Haag, T. H. "Nonpolluting Coatings and Coating Processes"; Plenum: New York, 1973. 20. McEwan, I. H. J. Paint Technol. 1973, 45, 33. 21. Leasure, E. L.; Finegan, P. M.; Calder, G. V. J. Water Borne Coat 1977, 1977, 4. 22. Klein, D. H.; Elms, W. J. J. Paint Technol. 1973, 45, 68. 23. Blank, W. J.; Hensley, W. L. J. Paint Technol. 1974, 46, 46. 24. Harren, R. E.; Flynn, R. W.; Levantin, A. M. Off. Dig. 1965, 37, 511. 25. Yunaska, M. R.; Gallagher, J. E. Resin Rev. 1969, 19, 3. 26. Bufkin, G.; Grawe, J. R. J. Coat. Technol. 1978, 50, 41, 67, 83. Ibid., 50, 70. Ibid., 50, 65. Ibid. 1979, 51, 34. 27. Emmons, W. D.; Mercurio, Α.; Lewis, S. N. J. Coat. Technol. 1977, 49, 65.


Chemistry and Technology of Acrylic Resins for Coatings - American

Recommend Documents