A na-eji mpempe akwụkwọ, akwa, ihe nkiri plastik mee teepu nwere akụkụ abụọ dị ka mkpụrụ, mgbe ahụ, a na-ekpuchikwa ụdị elastomer nke nrụgide na-enwe mmetụta na-emetụ n'ahụ ma ọ bụ ihe ntanye na-emetụ n'ahụ nke dị n'elu.Ihe ntanye nke nwere ụdị mpịakọta nwere akụkụ atọ: mkpụrụ, nrapado na akwụkwọ ntọhapụ (ihe nkiri).