Copolymer glass

Developments by BASF in high-impact propylene copolymers produced by reactive blending, random propylene copolymers, glass fibre-reinforced PP composites and PP foams are reported. Properties and applications of these materials are described. 4 refs. BASF AG... 

H. Suzuki and V.B.F. Mathot, An insight into the Barton equation for copolymer glass transition, Macromolecules, 22(3) 1380-1384, March 1989. 

Systems in which a polyolefin is the binder have attracted world-wide attention. These include the polyethylene—phenolic microsphere 74,115>, polyethylene or polypropylene—glass microsphere114116), polyethylene or polybutylene—PVC microsphere (containing isobutane)52), and polyethylene/vinyl acetate copolymer—glass microsphere11 systems. Syntactic foams have been made from polystyrene (and its copolymers with chlorostyrene or polychlorostyrene) and microspheres made from polyethylene or polypropylene46115 and foams from styrene/acrylonitrile 1171... 

In Table I the single-phase block copolymer glass transitions (Tg) or, where appropriate, the low and high observed TgS in the case of two phases, (Tg)L and (Tg)H, are presented. Bisphenol-A-poly carbonate homopolymer s Tg is approximately 145°C, some 20°C lower than (Tg)L. However, the (Tg)H falls quite close to that of homopolysulfone based on bisphenol-A, a point to which we shall later return. 

Capron . [Allied-Signal Croxton Carry Ltd.] Nylon 6 homopolymets, copolymers, glass and mineral-reinforced grades for inj. mdding and ex-ttusitm. 

PET scrap suitable for glycolytic recycle includes production waste, fibers, film, flake, and bottles. In a practical system, major contaminants are separated from feedstocks, e.g., bottle waste is cleaned and separated from a polyethylene base, paper labels, metallic caps, and liners. For many end uses, colored PET must also be segregated. (Highly modified copolymers, glass-reinforced resin, fiber, or fabric blends are not suitable for glycolysis. These can only be recovered by methanolysis/hydrolysis.) Since reaction time depends on surface area, PET feedstocks must be reduced to relatively small particles by grinding, cutting, etc. 

Several types of insulator materials— Teflon, polyethylene, polystyrene, silicon, dacron, ioplexes, ethylene-vinyl acetate and ethylene acrylic acid copolymers, glass, etc.—have been examined for their electrokinetic characteristics. In some of these cases, the surface charge characteristics have been modified by prior electrical or chemical treatment. The correlations which have been drawn between the electrokinetic and anti- or prothrombogenic characteristics of these materials are presented in the next section. 

In Fig. 7.70 the Barton equation for copolymer glass transitions is listed. It is based on the assumption that the four possible dyads in a copolymer, poly(A-co-B), have the following glass ttansitions AA (Tj = T aa). BB (T = T bb), AB, and BA (Tg = TgAB = T ba)- Inserting these three different glass transitions into the Gibbs-Di Marzio equation for the intermolecular effects, leads to ... 

SuzukiH, Mathot VBF (1989) An Insight into the Barton Equation for Copolymer Glass Transition. Macromolecules 22 1380-1384. 

J. P. Chen, A. F. Yee, and E. J. Moskala, The Molecular Basis for the Relationship between the Secondary Relaxation and Mechanical Properties of a Series of Polyester Copolymer Glasses , Macromolecules 32, 5944 5955 (1999). 

Johnston [7] took into account the chain sequence distribution of copolymers in the prediction of the glass transition temperatures. Sharma [8], and Sharms et al. [9] found that this model compared well with experimental data even for systems obtained from reversible copolymerization. Johnston s dyad model for prediction of copolymer glass transition temperature can be written as follows ... 

GLASS REINFORCED FLUOROPLASTICS FLUOROPLASTICS AND COPOLYMERS PVC AND COPOLYMERS GLASS REINFORCED PVC ALLYLS... 

ACRYLIC POLYURETHANES UREA-FORMALDEHYDE PVC 8i COPOLYMERS GLASS REINFORCED PVC CELLULOSICS... 

Glass transition temperature of stereoregular copolymer Glass transition temperature (Tg)... 

Polystyrene(SAN) Copolymer, Glass Fiber Reinforced PSCO-GFR... 

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