Observation of molecular chain scission during crazing of polystyrene

A series of gel permeation chromatographic (GPC) separations has been performed on polystyrene specimens in an attempt to discern whether or not mechanical crazing is accompanied by significant covalent bond scission. It was found that the extent of scission is not large but is indeed present in concentrations that are detectable by GPC. This suggests that molecular‐slippage‐only models of the crazing process are perhaps overly idealized and that crazing cannot take place in highly entangled polymer solids without some bond rupture.