PP-BSt copolymer is dependent on the concentration of pendant styrene
(crosslinker) units. High crosslinker content is needed in order to observe an
appreciable crosslinking reaction. It appears important to anneal the copolymer
film at temperatures above 160
C (beyond its melting temperature) to achieve high
Fig. 6 GPC curves of (a) PE and three linear poly(ethylene-co-1,4-divinylbenzene) copolymers,
containing (b) 1.5, (c) 2.3, and (d) 7.2 mol% DVB units, respectively (solvent, trichlorobenzene;
temperature, 135
C)
Fig. 7
1
H NMR spectrum of poly(ethylene-co-1,4-divinylbenzene) with 7.2 mol% DVB units
(solvent, C 2 D 2 Cl 4 ; temperature, 110
C)
250
T.C.M. Chung