Poly casting processes

Beaulne, M. and Milsoulis, E. 1999. Numerical simulation of the fihn casting process. Int. Poly. Proce.ss. XfV, 261-275. 

Wada and others (1966) indicated that the piezoelectricity of poly-oxymethylene (POM) markedly increases when a temperature gradient has been applied during the casting process, probably because of the thermal diffusion of ions in the film. 

Zhou, F., Gupta, S. K. and Ray, A. K. (2000). Multi-objective optimization of the continuous casting process for poly (methyl methacrylate) using adapted genetic algorithm, J. Appl. Polym. Sci., 78, pp. 1439-1458. 

Moreover, blends of incompatible homopolymers can be microstructured into honeycomb arrays by the combination of BFs and phase separation of the polymer blend. For instance, Cui et al. studied the formation of porous films from blends of PS and poly(2-vinylpyridine) (P2VP) [73-75], The authors observed that during the casting process under moisture, P2VP stabilizes the water droplets because it is more hydrophilic than PS. The domains were reassembled by the water droplets and then ordered holes enriched in P2VP were formed after solvent and water evaporated [76], Similar studies have been performed using other blends of homopolymers with different polarities for the BF formation (eg, PS/PMMA [77] or PMMA/poly(vinyl butyral) [78]). 

Solvent effects can influence the outcome of the casting process because of the intervention of polymer-solvent interactions in addition to the polymer-polymer interactions. Polymer-solvent interactions influence the viscosities of poly-... 

The spin casting process can be carried out in a heatable centrifuge using a spinning cell of the desired sample dimensions. It is advisable to cover the inner wall of the cell with a strip of poly(tetrafluoroethylene) foil (Teflon) in order to avoid adherence between the casted elastomer film and the wall and allow for easy removal. The ends of the strip should not overlap and they should be marked so that they can be recognized easily after synthesis. 

The poly(vinylacetate)-polypyrrole composite film also showed high electrical conductivity of about 10 S/cm which resulted from the polypyrrole network structure formed from the spinodal decomposition during the casting process. 

To solve this problem, we recently developed a lab scale solution film casting process to fabricate novel poly(arylene ether sulfone) copolymer membranes in continuous way. A small reverse roll casting machine was built and used to cast membranes with vmiform, defect free membranes with thickness about 25 to 50 microns. Efforts were also be made to evaluate the properties of the films, including proton conductivity, water uptake, mechanical properties and morphology of the membranes, and compare them with that of hand cast films cast with the same or similar polymer samples. The preliminary results obtained were reported here. 

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