Probably because the hydrogen bond that TPS has higher strength, TPF product TPS has a sort of molecular chain straps that are closer together than the TPF, so every piece of work when TPS voltage absorption less.
TPS is probably due to the hydrogen bond is stronger than the specimen TPF TPS with a sort of chain molecules closer together than on the TPF shock absorbing material so TPS is less.
Probably because TPS that hydrogen with high strength than TPF specimens TPS is a sort of molecular chain, which close together TPF when that target TPS thus absorbs impact force less