Haufinyane tjena, moreki o ile a botsa theko ea thapo ea polypropylene, moreki ke moetsi oa thapo ea ho ts'oasa litlhapi kantle ho naha, hangata e sebelisoang ke thapo ea polyethylene, empa thapo ea polyethylene e boreleli, ho bonolo ho lokolla ka mor'a ho knotting, 'me molemo oa thapo e sephara ke hore monofilament ea thapo e mahoashe, ho kokota ha ho bonolo ho thella.Empa polypropylene e boima ho feta polyethylene.Ka khopolo, mokhoa oa molek'hule oa propylene ke CH3CH2CH3, 'me mokhoa oa molek'hule oa ethylene ke CH3CH3.Polypropylene e na le athomo e le 'ngoe ea carbon ho feta polyethylene, kahoo boima ba thapo ea polypropylene bo boima ho feta polyethylene.

Sebopeho sa polyethylene ke se latelang:

—(CH2-CH2-CH2-CH2)n—-

Sebopeho sa polypropylene ke se latelang:

—(CH2-CH(CH3)-CH2-CH(CH3)-CH2-CH(CH3))n—-

E ka bonoa ka sebopeho sa hore polypropylene e na le ketane ea lekala ho feta polyethylene.Ka mor'a ho etsa thapo, ka lebaka la karolo ea ketane ea lekala, thapo ea polypropylene e na le tsitsipano e matla ho feta polyethylene, 'me ha ho bonolo ho thella.Boima ba polypropylene ke 0.91 mme boima ba polyethylene ke 0.93, kahoo polyethylene e lokela ho ba boima ho feta.

Thapo ea polyethylene e tenyetseha, e boreleli ebile e bonolo ho feta polypropylene.