改性淀粉与丙烯酸接枝共聚物的合成及应用性能

研究经过热处理的改性淀粉与丙烯酸的接枝共聚反应。接枝共聚产物在 790cm-1、85 0cm-1(物理改性淀粉的特征吸收峰 )和 172 0cm-1(聚丙烯酸的特征吸收峰 )处的红外光谱验证了接枝共聚反应的发生。探讨了引发剂过硫酸铵浓度、丙烯酸浓度、反应温度和反应时间等因素对接枝率和接枝效率的影响。当 ρ(淀粉 ) =70 g/L、t =6 0℃、反应时间为 3h、c〔(NH4) 2 S2 O8〕 =3 0× 10 -3 mol/L、c(丙烯酸 ) =0 4 2mol/L时 ,合成胶粘剂的初粘力为 10 0 % ,吸水率为 15 0 14 % ,吸油率为 2 0 6 % ,其压制的纸板冲击强度为 3 2 5kN/m ,拉伸强度为 3 75MPa ,与纯淀粉粘接剂相比较 ,所压制纸板的应用性能得到较大的改善。

Synthesis and Application of Grafting Copolymer of Modified Starch and Acrylic Acid

Grafting copolymerization of acrylic acid and modified starch by heat treatment was investigated. Realization of the reaction was proved by infrared spectrum. Effects of concentrations of monomer and initiator,reaction temperature and reaction time on grafting efficiency and graft rate were studied.When concentrations of acrylic acid,ammonium persulfate and modified starch are 0 42 mol/L,3 0×10 -3 mol/L and 70 g/L respectively,at reaction temperature of 60 ℃ and reaction time of 3 h,the synthesized adhesion agent has an adhesion ratio of 100%, water absorption of 150 14% and oil absorption of 2 06% .Mixture of the grafting copolymer and paper pulp is pressed into a board whose impact strength and stress strength are 3 25 kN/m and 3 75MPa respectively.These properties are superior to that with an adhesion agent of non grafted modified starch.