Polymethylmethacrylate stabilizer from

Stability Unstable in air. Protect from water or moisture. Store away horn heat or ignition sources and sulfur compounds. Reacts with sulfur and sulfur compounds, producing highly toxic VX or VX-like compounds. It completely dissolves polymethylmethacrylate. It is incompatible with calcium hypochlorite (HTH), many chlorinated hydrocarbons, selenium, selenium compounds, moisture, oxidants, and carbon tetrachloride. 

The other kind of systems largely studied, consists of polymethylmethacrylate (PMMA) or silica spherical particles, suspended in organic solvents [23,24]. In these solvents Q 0 and uy(r) 0. The particles are coated by a layer of polymer adsorbed on their surface. This layer of polymer, usually of the order of 10-50 A, provides an entropic bumper that keeps the particles far from the van der Waals minimum, and therefore, from aggregating. Thus, for practical purposes uw(r) can be ignored. In this case the systems are said to be sterically stabilized and they are properly considered as suspensions of colloidal particles with hard-sphere interaction [the pair potential is of the form given by Eq. (5)]. 

Predesigned particles of impact modifiers are based on core-shell technology. Core is involved in impact modification and shell improves adhesion between PVC and impact modifier particles.Three major combinations are used methacrylate-butadiene-styrene, MBS, which has a core made out of butadiene-styrene copolymers and shell made out of methylmethacrylate-styrene copolymer, acrylic impact modifiers, AIM, which have a core made out of acrylic and shell from polymethylmethacrylate, and silicone-acrylic have multilayer structures with silicone-acrylic in the core. MBS has excellent compatibility with PVC, similar to ABS, which is used as an impact modifier of PVC, as well. In both cases of ABS and MBS, weather resistance is lacking, therefore they are used for indoor applications only. At the same time, MBS gives translucent to crystal clear products, whereas with AIM, only translucent products are possible. In order to improve optical properties of AIM, it has to be reformulated. For transparent products, the core is made out of acrylic-styrene copolymers. Comparing silicone and all acrylic impact modifiers, PVC containing silicone-based products has superior low temperature impact properties. The incorporation of silicone into an acrylic impact modifier provides excellent weatherability, and thermal stability. It has shown improved retention of impact after outdoor weathering in PVC. ... 

It is clear from Equation 14.18 that when the Flory-Huggins interaction parameter, % is <0.5, that is, the chains are in good solvent conditions, is positive, and the interaction is repulsive and increases very rapidly with decreasing h, when the latter is lower than 28. This explains why polymeric surfactants such as Hypermer CG6 (a graft copolymer of polymethylmethacrylate backbone and PEO side chains, produced by ICl) are ideal for stabilizing dispersions in aqueous media. For stabilization of dispersions in nonaqueous media, such as w/o emulsions, the stabilizing chains have to be soluble in the oil phase (normally a hydrocarbon). In this case, polyhydroxystearic acid (PHS) chains are ideal. A polymeric surfactant such as Aralcel P135 (an ABA block copolymer of PHS-PEO-PHS produced by ICl) is an ideal w/o emulsifier. 

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