Environmental Polymers Group

C) [73], releasing water and forming conjugated double bonds. PVA films were thus produced by an expensive solution casting process. Several companies developed biodegradable PVA that can be processed as a thermoplastic Environmental Polymers Group (EPG) in the UK, Idroplast in Italy, Millenium Polymers in the USA and PVAX Polymers in Ireland [74]. 

Environmental Product Declaration Environmental Polymers Group Expanded polystyrene... 

Environmental Polymers Group has patented an extrusion process together with PVOH formulation technology to produce thermoplastic PVOH pellets which can be converted into film and sheet products [67]. EPG PVOH, which is typically 40-50% crystallinity, can be used to produce films with tensile and tear strengths superior to PE and PVC (see Table 6.7). 

As Table 21-1 suggests, molecular chlorine is a tremendously versatile industrial chemical. This element is a leading industrial chemical because of this versatility rather than any single application, although polymers account for about one third of its uses. In recent years, however, the industrial use of chlorine has come under strong attack from many environmentally conscious groups. One major reason is that dioxins, one class of by-products of chlorine reactions, have a very detrimental effect on biosystems. The controversy over industrial chlorine is described in our Chemistry and the Environment Box on page 936. 

Vallee-Rehel, K., Langlois, V., Guerin, P. Contribution of pedant ester group hydrolysis to the erosion of acrylic polymers in binders aimed at organotin-free antifouling paints. Journal of Environmental Polymer Degradation, 6(4)... 

Euheler JP, Bernhard M, Zok S, Knepper TN (2010) Environmental biodegradation of synthetic polymers II. Biodegradation of different polymer groups. Trends Anal Chem 29 84-99... 

An alternative route starts with a carboxy-terminated oligomer [36], This is reacted with glycidyl methacrylate to provide the methacrylate-terminated polymer. The resulting linkage is susceptible to hydrolysis, so the hydroxy group may be reacted with an isocyanate to improve environmental resistance (Scheme 3). 

In many cases, it is possible to replace environmentally hazardous chemicals with more benign species without compromising the technical and economic performance of the process. Examples include alternative solvents, polymers, and refrigerants. Group contribution methods have been conunonly used in predicting physical and chemical properties of synthesized materials. Two main frameworks have... 

As mentioned previously, additive treatments involve the application of a polymer to the fibre. This is usually prepared before application and contains reactive groups. However, it is also possible to form the polymer in situ within the fibres. The traditional approach is to apply the polymer after a subtractive oxidation treatment but environmental concern over A OX problems is increasing demand for additive treatments that can stand alone. There is no denying that the oxidative step can facilitate subsequent treatment with a polymer, since the scission of cystine disulphide bonds to yield cysteic acid residues provides useful reactive sites for crosslinking or anchoring the polymer. 

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