Styrene-modified alkyd resins

Styrene-Modified Alkyd Resins. Styrene was first copolymerized with drying oils in the early 1940s. These binders had a substantially improved drying behavior and resistance to water and chemicals compared with untreated oils. The first patents for the production of styrenated alkyd resins were granted in the United Kingdom in 1942 [2.63]. Mixtures of styrene and a-methylstyrene are also used for a more reliable reaction vinyltoluene yields copolymers with improved thinnability in mineral spirit and pigment absorption. 

Styrene [100-42-5] is a colorless liquid that acts as a solvent for unsaturated polyester resins. Styrene is stabilized by the manufacturer to avoid polymerization on storage. Feedstock for chemical syntheses (polymers and copolymers, styrene-modified alkyd resins and oils). 

Modified alkyd resins In this group one finds styrenated alkyds, vinyl toluenated alkyds, oil-modified vinyl resins, acrylic alkyds, silicone alkyds and polyurethane alkyds. The modifying component usually has a number of effects. It always increases the molecular weight of the alkyd polymer, and may impart hardness, durability, or chemical resistance. It also affects the solubility of the polymer in solvents. 

The solvency of cycloaliphatic hydrocarbons is between that of aliphatic and aromatic hydrocarbons. They have a high solvency for fats, oils, oil-modified alkyd resins, styrene-modified oils and alkyd resins, bitumen, rubber, and other polymers. Polar resins (e.g., urea-, melamine-, and phenol-formaldehyde resins), as well as alcohol-soluble synthetic resins and cellulose esters are, however, insoluble. 

Compared to aliphatic hydrocarbons, aromatic hydrocarbons (DIN 51633) have a higher solvency for oils, castor oil, oil-modified alkyd resins, styrene-modfied oils and alkyd resins, saturated polyester resins, polystyrene, poly(vinyl ethers), polyacrylate and polymethacrylate esters. poly(vinyl acetate), vinyl chloride and vinyl acetate copolymers, and many low-polarity resins. 

The alkyd resins are of value because of their comparatively low cost, durability, flexibility, gloss retention and reasonable heat resistance. Alkyd resins modified with rosin, phenolic resin, epoxy resins and monomers such as styrene are of current commercial importance. 

Phthalate based polycondensate resins, modified with unsaturated fatty acids and styrene as well as vinyltoluene have many applications in the form of paints and lacquers as alkyd resins". 

For alkyd resins, non-benzenoid (maleic type) care must be taken to see that comparability is maintained over a period of years. Styrene alkyds are included in the total for some years. IMaleic alkyds, modified with rosin and rosin ester, are included in the annual figures and in the monthly figures. Figures on maleic alkyds are available from 1938 on 11),... 

Alkyd resins modified with compounds such as styrene, vinyl toluene, and methyl methacrylate have become more important in... 

DIN 53183 defines an alkyd resin as follows Alkyd resins are synthetic polyester resins produced by esterifying polyhydric alcohols with polybasic carboxylic acids. At least one of the alcohols must be trihydric or higher. Alkyd resins are always modified with natural fatty acids or oils and/or synthetic fatty acids. In order to obtain particular application technology properties, alkyd resins may be additionally modified with compounds such as resin acids, benzoic acid, styrene, vinyltoluene, isocyanates, acrylic, epoxy, or silicone compounds. ... 

The properties of bitumen paints (Section 2.14.2) can be favorably modified and adjusted to suit practical requirements by combination with other film-forming substances. For example, the thermoplasticity can be reduced and/or mechanical properties (e.g., hardness, extensibility) can be improved by adding polymers such as polyethylene, polypropylene, polyisobutene, and styrene-butadiene copolymers. The chemical resistance can also be improved high-quality corrosion protection coatings can be obtained by combination with alkyd resins. 

Another classification is unmodified or modified alkyds. Modified alkyds contain other monomers in addition to polyols, polybasic acids, and fatty acids. Examples are styrenated alkyds and silicone alkyds. Since they are closely related to alkyd resins, uralkyds and epoxy esters are also discussed. 

Polyesters are thermosetting resins produced by the reaction of mixtures of glycols and dibasic acids. The compound is comparable to an alkyd resin used in paints. However, it is further modified by dissolving it in styrene, and it is cured into a thermosetting plastic by the addition of catalysts and accelerators. The plastic can be modified with additives similar to those used in the PVC compounds. 

Styrenated fatty acids and alkyd resins spectrophoto-metric analysis using a modified Kappelmeier procedure, with ultraviolet determination of polymerized styrene Styrene and fumerate in esters and resins 0.1-2% styrene in polystyrene at 250-260 m/i direct determination polystyrene in a copolymer in chloroform solution at 269 mu partial separation, nitration, and determination as neutralized p-nitrobenzoic acid, of bound styrene in raw and cured polymers, using a three-wavelength ultraviolet measurement to check for unexpected interfer-... 

Alkyd chemistry lends itself to further modification beyond choice of polyol, dibasic acid, and drying oil. Vinyl-modified alkyds, for example, are produced for more durable and quicker drying films, although with some sacrifice in crosslinking rate and consequent development of solvent resistance. Styrene, vinyl toluene, and methyl methacrylate are the most commonly used modifiers. In the presence of a free radical initiator, vinyl polymer will graft onto the alkyd. Tack-free time (i.e. a surface-dry film) may be reduced from 4 to 6 hoius for an unmodified alkyd to 1 hour in styrenated form. Acrylics, silicones, phenolic resins, and natural resins are likewise used to tailor film gloss, flexibility, durability, and drying time for certain applications. 

Use Polystyrene SBR, ABS, and SAN resins protective coatings (styrene-butadiene latex, alkyds) styrenated polyesters rubber-modified polystyrene copolymer resins intermediate. 

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