In order to clarity tne effects ot entanglement species on nucleation ot polymers, we stuaiea tne growtn rate ot spneruute G of cyclic ana linear polyethylenes (C-PE and L-PE) from the melt as a function of degree of supercooling A T by means of polarizing optical microscope. We prepared several C-PEs with different weight average molecular weights M w=9300, 43600 and 86500, and L-PE with A/,=44000. G of all the sample were obeyed the equation, G = G 0 exp (-B/△T).BoîC-PE gradually increased with increasingM w. B is proportional to the surface free energy of the end surface of the nucleus, and this indicates that the regularity of folding surface increased with increasing M w. We consider that topological constraint of cyclic polymer becomes large with decreasing M., of the cyclic polymer. On the other hand, for C-PE and L-PE having almost the same M w (=44 k), G 0 of C-PE is much less than that of L-PE. Due to the topological constraint of cyclic polymer, we speculated that the adsorption mode on the crystal surface of C-PE is different than that of L-PE.
- Cyclic polymer
- Growth rate
ASJC Scopus subject areas
- Chemical Engineering (miscellaneous)
- Materials Science (miscellaneous)
- Environmental Science(all)
- Polymers and Plastics