Question

Poly(vinyl acetate) of number-average molecular weight of 100,000 is hydrolyzed to poly(vinyl alcohol). Oxidation of the latter with periodic acid to cleave 1,2-diol linkages yield a poly(vinyl alcohol) with X_n = 200. Calculate the percentage of head-to-tail and head-to-head linkages in the poly(vinyl acetate).

Answer 1

Poly(vinyl)alcohol is given by the head to tail linked polymer. Therefore number of vinyl acetate monomeric units involve in forming Poly(vinyl)alcohol is 200.

The weight of one vinyl acetate unit=86 g/mol

Therefore the weight of 200 units=86*200=17200

The weight of the poly vinyl acetate polymer only due to this=100000-17200=82800

Therefore the percentage of head to tail linkages=(17200/100000)*100=17.2%

the percentage of head to head linkages=(82800/100000)*100=82.8%