Single chain polystyrene particles were obtained by dilute solution casting method.The sample with both single chain polystyrene particles and multi-chain (more than 1000 molecular chains) polystyrene particles was obtained by a little more concentrate solution.Force modulation technique showed that single chain polystyrene particles were softer than multichain polystyrene particles.On the other hand

nanoindentation experiments on multi-chain particles and bulk polystyrene manifested that the elastic modulus of multi-chain polystyrene particles was very close to that of bulk polystyrene.Therefore

it was concluded that single chain polystyrene particles were softer than bulk polystyrene

which indicated that the desity of intrachain entanglement points in the single chain polystyrene particles was not as large as that of the interchain entang lement points in the bulk sate.