Saran, polyvinylidenechloride

Factors of 1/100 and more were observed in the adsorption rates for bulky molecules like 3,3-diethylpentane compared to linear and planar molecules. The rate differences were attributed to steric limitations on the adsorption of the bulkier molecules. Separation of n-butane from isobutane was accomplished both on Saran- and other polyvinylidenechloride-derived carbons (9-11). 

Polyvinylidenechloride, PVDC, was discovered in 1838 by Regnault but commercialized 100 years later as Saran . The commercial PVDC is modified by the incorporation of either 15-20 wt% vinyl chloride, or 13 wt% vinyl chloride and 2 wt% acrylonitrile. PVDC blends are summarized in Table 1.32. 

Polyvinylidenechloride (Saran ) Polyolefins Polyethylene Good Good Resistant Resistant except NH4OH Resistant Resistant Unstable Resistant... 

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