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Additive High molecular mixtures

The preparation of high molecular weight PPT in HMPA/NMP shows a strong dependence of inherent viscosity on reactant concentrations. In 2 1 (by volume) HMPA/NMP, the highest inherent viscosity polymer is obtained when each reactant is present in concentrations of ca 0.25 M higher and lower concentrations result in the formation of polymer of lower inherent viscosities. A typical procedure is as foUows 1,4-phenylenediamine, HMPA, and NMP are added to an oven-dried resin ketde equipped with a stirrer and stirred for ca 15 min with cooling to — 15°C, foUowed by the addition of powdered terephthaloyl chloride to the rapidly stirred solution. The reaction mixture changes to a thick, opalescent, paste-like gel in ca 5 min. [Pg.65]

Plastics and Resins. Plastics and resin materials are high molecular weight polymers which at some stage in their manufacture can be shaped or otherwise processed by appHcation of heat and pressure. Some 40—50 basic types of plastics and resins are available commercially, but HteraHy thousands of different mixtures (compounds) are made by the addition of plasticizers, fillers, extenders, stabilizers, coloring agents, etc. [Pg.369]


See other pages where Additive High molecular mixtures is mentioned: [Pg.37]    [Pg.39]    [Pg.262]    [Pg.296]    [Pg.221]    [Pg.315]    [Pg.399]    [Pg.333]    [Pg.313]    [Pg.314]    [Pg.110]    [Pg.54]    [Pg.331]    [Pg.204]    [Pg.219]    [Pg.39]    [Pg.110]    [Pg.195]    [Pg.201]    [Pg.366]    [Pg.376]    [Pg.685]    [Pg.44]    [Pg.116]    [Pg.364]    [Pg.32]    [Pg.235]    [Pg.22]    [Pg.18]    [Pg.52]    [Pg.56]    [Pg.21]    [Pg.123]    [Pg.101]    [Pg.157]    [Pg.143]    [Pg.246]    [Pg.118]    [Pg.155]    [Pg.191]    [Pg.147]    [Pg.168]    [Pg.26]    [Pg.72]    [Pg.113]    [Pg.220]    [Pg.156]    [Pg.488]    [Pg.214]   
See also in sourсe #XX -- [ Pg.466 ]




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Molecular addition

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