Influence of isotactic polypropylene grafted with styryl-group on the polymer crystallization behavior

4-Furfuryloxymethylstyrene (S-f) grafted isotactic polypropylene (iPP-g-S-f) was prepared by melt grafting reaction. The crystallization temperature of iPP after grafting increased to similar to 130 degrees C. The isothermal and non-isothermal crystallization kinetics of iPP-g-S-f containing up to 1.50 mol% grafted S-f groups were compared with that of virgin iPP, and the isothermal and non-isothermal crystallization kinetics parameters of the polymers, including the fold surface free energy sigma(e), the chain folding work q, and the crystallization activation energy Delta E, were calculated by Lauritzen-Hoffman theory and Kissinger method respectively. The results showed that iPP-g-S-f exhibited a unique self-nucleation phenomenon, which accelerating the crystallization rate of iPP and produced tiny crystal morphology than that for iPP. The introduction of only 0.23-1.50 mol% grafted S-f groups reduced the sigma(e) of the crystals by 44-57%. This might provide guidance for the design of polymer crystallization rate by controlling the molecular structures.

Automated summary

4-Furfuryloxymethylstyrene (S-f) grafted isotactic polypropylene (iPP-g-S-f) was prepared by melt grafting reaction. The crystallization temperature of iPP after grafting increased and the crystallization rate was accelerated, resulting in smaller crystal morphology. The introduction of a small amount of S-f groups reduced the surface free energy of the crystals.