Ethylene polysulphone

Tension Above materials plus High-density polyethylene Polypropylene Acetal polymers Aliphatic polyamides (nylons) PPO Poly(ethylene terephthalate) Polysulphones... 

It has already been shown (e.g. Chapters 20 and 21) that the insertion of a p-phenylene into the main chain of a linear polymer increased the chain stiffness and raised the heat distortion temperature. In many instances it also improved the resistance to thermal degradation. One of the first polymers to exploit this concept commercially was poly(ethylene terephthalate) but it was developed more with the polycarbonates, polysulphone, poly(phenylene sulphides) and aromatic polyketones. 

Certain polymers have come to be considered standard building blocks of the polyblends. For example, impact strength may be improved by using polycarbonate, ABS and polyurethanes. Heat resistance is improved by using polyphenylene oxide, polysulphone, PVC, polyester (PET and PBT) and acrylic. Barrier properties are improved by using plastics such as ethylene vinyl alchol (EVA). Some modem plastic alloys and their main characteristics are given in Table 1.2. 

Under some conditions, ethylene and vinyl compounds (vinyl chloride, styrene, acrylic acid, chloroprene, etc.) can be copolymerized with S02 [63-65]. During synthesis of this type of polysulphone, carbon radical centres alternate with... 

Bauminger et al. 0,40 find a spectrum at 4 K composed of doublets A and B for Nafion 110 equilibrated with a methanol solution of FeCl3. Parameters were the same as for the aqueous exchanges, but the intensity ratio was somewhat different. These authors have also examined Redcat poly(ethylene sulphonic acid) and sulphonated polysulphone membranes where they again find two doublets, but A has QS = 0.60(3) mm/s. 

An obvious need exists for membranes with improved permeability and permselectivity. In addition to several earlier pieces of work contained in ref. Zg and Zh studies involving radiation-modified poly(vinyl alcohol) ordered polycarbonates " and cellulosic ion-exchange membranes have been reported. A variety of reports have appeared of the evaluation of existing polymers, such as polysulphone, in biomedical applications for which they have not previously been used, and of the synthesis of new polymers which may find use in the biomedical area. Examples include polyorganophosphazenes, biodegradable poly(ethyene oxide)-poly(ethylene terephthalate) copolymers, collagen copolymers, block copolymers of l,4-bis(acryloyl) piperazine-AW -dimethylethylene diamine and styrene, and >olymers derived fi om a miscellany of heterocyclic monomers. Information on chemically modified polymers designed for biomedical use is also contained in Chapter 16 of this Volume. 

The materials examined were high and low density polyethylene, silvered fluorinated ethylene propylene teflon blanket material, polysulphone matrix resin/graphite fibre reinforced composites, poly(methyl methacrylate) and silicones [326, 450,1326, 2314]. Long term exposed polymeric samples show loss of surface integrity and surface erosion. The radiation combines with atomic oxygen to initiate chain scission and crosslinking, both of which greatly affect the polymers structural properties. 

It has been reported that films of the thermoplastics poly(ethylene oxide) [535] and polysulphones [534, 536, 543] can be used to monitor solar UV... 

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