Study Of 2-Hydroxyethyl Methacrylate Melt Grafting Isotactic Polybutene-1

2-Hydroxyethyl Methacrylate (HEMA)/co-monomer melt grafting of isotactic polybutene-1(iPB-1) was prepared in Haake torque rheometer by using dicumyl peroxide (DCP) as initiator, styrene (St) or a-Methyl styrene (AMS) as co-monomer. The influence of reaction temperature, initiator, monomer, co-monomer content on grafting degree (Gd), grafting efficiency and Melt Flow Rate (MFR) of the resulted grafting copolymer were investigated respectively. The results showed that the grafting laws were similar for different co-monomer grafting system, but they had different the best ratio of raw materials. As a comonomer, styrene can remarkably enhance the grafting degree and grafting efficiency. Side reaction was severe degradation in St co-monomer grafting system.The flowing property and Surface property of resulted grafting copolymer (iPB-g-HEMA) were investigated respectively. The experimental results showed that the monomer (HEMA) and co-monomer (St or AMS) grafted to the polymer chain successfully. Differential scanning calorimetry showed that compared with iPB-1, the thermal property of iPB-g-HEMA had a big change, the melting point decreased, degree of crystallinity, the crystallization temperature, the melting enthalpy and enthalpy of crystallization raised. Melt Flow Rate (MFR) showed different co-monomer system had different flowing properties, thus obtained resulted grafting co-polymer with different molecular weight to achieve a controllable effect. Meanwhile, the surface polarity of iPB-g-HEMA which was characterized by the contact angle of iPB-g-HEMA with water increased with increasing grafting degree.The crystallization property of iPB-g-HEMA was studied, The research of the non-isothermal crystallization showed that the crystallization peak shifted to lower temperature, and the crystallization peak broadened as the crystallization rate increased. Under the same cooling rate, compared with iPB-1, the Summary crystallization time was shortened. The Ozawa’s results showed that under the same temperature, crystallization rate of iPB-g-HEMA was faster than that of iPB-1 while the crystallization rate required to reach the same crystallinity in one unit time was smaller than that of iPB-1. The non-isothermal crystallization activation energy of iPB-1 and iPB-g-HEMA were -58.60KJ/mol and -149.95KJ/mol respectively by Kissinger’s equation. The non-isothermal crystallization activation energy of iPB-1 and iPB-g-HEMA were -41.74KJ/mol and -134.65KJ/mol respectively by Avrami’s equation. The crystallinity activity energy of iPB-g-HEMA was lower than iPB-1. The research of the isothermal crystallization showed that the isothermal crystallization of the same sample at different temperature, the crystallization time added and the crystallization rate decreased as the crystallization temperature raised. For the different samples at the same crystallization temperature, the isothermal crystallization process shortens and the rate of crystallization of Form Ⅱ quickened with grafting degree increased. The isothermal crystallization activation energy of iPB-g-HEMA with different grafting degrees 0.17%,0.93%,1.30% and 2.00% were -294.90KJ/mol,-311.60KJ/mol,-346.51 KJ/mol and -361.96 KJ/mol respectively. It showed that the high grafting degree samples can more esaily crystallize than that of the low grafting degree sample’s.