多巴胺改性滑石粉对聚乳酸/聚丁二酸丁二醇酯共混体系结晶行为及流变性能的影响

通过熔融共混法制备了聚乳酸(PLA)/聚丁二酸丁二醇酯(PBS)/多巴胺改性的滑石粉(D-Talc)共混试样,采用红外光谱(FT-IR)、偏光显微镜(POM)、差示扫描量热(DSC)以及流变测试系统考察了D-Talc对共混试样结晶行为及流变性能的影响。FT-IR结果表明,聚多巴胺已成功包覆在滑石粉表面,且未对滑石粉的原结构造成破坏。POM结果表明,DTalc在共混试样中起到成核剂的作用,当D-Talc含量为0.1 phr时成核效果显著,且能明显提高共混试样的结晶速率。DSC结果表明,D-Talc加入后共混试样在降温过程中出现明显的结晶峰,且共混试样的起始结晶温度(Ts)、结晶峰温度(Tp)与熔融温度(Tm)均向高温方向移动。流变测试结果表明,随着D-Talc含量的增加,共混试样的成核温度(Tb)、晶体的形成及生长温度(Tc)均向高温方向移动;黏度(η)随剪切速率(γ)的增加而减小,呈现出非牛顿流体的特性。

Effect of Dopamine Modified Talcum Powder on the Crystallization Behavior and Rheological Properties of PLA/PBS Blends

The poly(lactic acid) (PLA)/poly(butylene succinate) (PBS) /dopamine modified talcum powder (D-Talc) blends were prepared by melt blending.The effects of D-Talc on crystallization behavior and rheological properties of blends were investigated by FT-IR,POM,DSC and theological test system.FT-IR results show that poly(dopamine) is successfully coated on the surface of talc powder,and do not cause damage to the original structure of talc powder.POM results show that D-Talc plays a role of nucleating agent in the blend samples.When the content of D-Talc is 0.1,the nucleation effect is remarkable,and the crystallization rate of the blend is obviously increased.DSC results show that the crystallization peaks appear in the cooling process after the addition of D-Talc,and the crystallization temperature Ts,the peak temperature Tp and the melting temperature (Tm) of the blend samples move to the high temperature.Rheological test results show that the nucleation temperature (Tb),crystal formation and growth temperature (Tc) of the blend move to high temperature with the increase of D-Talc content.Viscosity (η) with shear rate (y) decreases with the increase of shear thinning,showing the characteristics of non-Newtonian fluid.