Stability: acrylics

Rigid PVC is polymerized at 55-70°C and then compounded with organotin stabilizer, acrylic processing aid, lubricants, and optionally with rubbery impact modifier. 

INTEX STABILIZER 17 is an additive to a pad bath designed to give better heat and shear stability to emulsion systems in the presence of inorganic salts. It will stabilize acrylic soil release polymers, acrylic polymers, vinyl acetate polymers, styrene butadiene polymers, urethane emulsions and silicone emulsions. 

Figure 4. Oxygen absorption data for stabilized acrylate coating resin aged at 140 C.

Distear Uiiodipropionate, 4-Dodecyk)xy-2-hydroxybenzophenone, Dovetphos 4-HR Dovetphos 4-HR Plus Naugard BHT Ralox LC Santonox TBMC Ultranox 627A Weston TNPP stabilizer, acrylate-based automotive paints... 

Benzophenone-3 2(2 -Hydroxy-3, 5 (1,1-dimethylbenzylphenyl) benzotriazole UV stabilizer, acetals 2-[2-Hyd roxy-3,5-d i-( 1,1 -d i methyl benzyl) phenyll-2H-benzotriazole 2-Hydroxy-4-isooctoxybenzophenone UV stabilizer, acrylates 2-Ethyl, 2 -ethoxy-oxalanilide UV stabilizer, acrylics 2-[2-Hydroxy-3,5-di-(1,1-dimethylbenzyl) phenyll-2H-benzotriazole Octrizole UV stabilizer, adhesives Benzophenone-12 Isocyanatopropyltriethoxysilane UV stabilizer, alkyds... 

Stabilized acrylic fibers are extremely hygroscopic [196], gaining about 8% in moisture and elongating about 15% and can be considered as plasticized material. PAN is strongly plasticized by water. 

Chen et a/ (1981) [201] studied the effect of decolorizing with NaOCl (5.25% available chlorine) on partly or fully stabilized acrylic fibers, heated for various times at 220-250°C. With lightly stabilized fibers, decolorization takes place in two steps—an incubation period with slight decolorization followed by a further incubation period and then gradual decolorization, whereas, with the fully stabilized fiber, the two processes occur simultaneously. 

Acrylic latexes are used for exterior paints because of their resistance to photodegradation and hydrolytic stability. Acrylic latex paints are useful for alkaline substrates such as masonry and galvanized metal. Acrylic and styrene-acrylic... 

Chain transfer in acrylic polymerizations was measured by the amount of gel in the latex products (Table II) (77). Reaction temperature, monomer feed time, and percent CAM have all been found to influence gel content. No gel was observed in surfactant stabilized acrylic latexes with CAM concentrations at or less than 1 phm, regardless of feed time or polymerization temperature. With CAM concentrations between 5 and 10 phm, the acrylic polymerizations had more than 60% gel when the reaction temperatures were above 65°C, and a monomer feed time of two hours. Gel was also observed to increase in 5 phm CAM latexes when the feed time was increased to greater than three hours. Latexes containing higher gel contents produce marginal particle coalescence resulting in poor scrub resistance. Conversely, low polymerization temperatures (such as 45T) with moderate amounts of CAM (5-10 phm) and short monomer feed times (less than three hours), resulted in latexes that had complete coalescence and exhibited good scrub resistance. 

A wide variety of polymers is used for lacquers. Newer systems favor acrylic polymers for their superior chemical stability. Acrylic lacquers may also incorporate a curing agent [1] such as hexamethoxymelamine, which crosslinks the him in a subsequent baking operation. Crosslinking toughens the him and improves solvent resistance. 

Merlatti, C., Perrin, F., Aragon, E., Margaillan, A. Natural and artificial weathering characteristies of stabilized acrylic-urethane paints. Pol) . Degrad. Stab. 93, 896-903 (2008)... 

The principal monomers butadiene, styrene, vinyl acetate, (meth)acrylates and acrylonitrile essenhally determine the material properties of films made from the corresponding dispersions the glass transition temperature, the water absorption capacity, the elasticity, etc. Auxiliary monomers, which are only used in a small proportion, usually <5 %, control important properties such as colloid-chemical stabilization (acrylic acid, methacrylic acid, acrylamide, methacrylamide), crosslinking within the particles (difunctional acrylates, divinylbenzene, etc.) or hydrophilic properties (OH-containing monomers, such as hydroxyacrylates). Reactive monomers which still contain a latently reactive group even after incorporation into the polymer, for example glycidylmethacrylate or N-methylol(meth)acrylamide, can form a network between various particles and polymer molecules after film formation. 

Latex paint Obtained by emulsion polymerizing. A suitable monomer in water. The final material is a stable emulsion of polymer particles coalesce, giving a strong film with a gloss. To give abrasion resistance to the film, sometimes inorganic fillers such as CaCOa are added. Because of their chemical stability, acrylic emulsions are preferred. 

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