豆蔻酸盐/磷酸酯羟基铝诱导PP结晶行为影响

Effect of myristic acid salts/phosphate hydroxyl aluminum on crystallization behaviors of PP

为了研究不同金属种类的豆蔻酸盐与双[2,2′-亚甲基-双(4,6-二叔丁基苯氧基)磷酸]羟基铝(APAl-OH)复配后对聚丙烯(PP)结晶行为的协效作用,将一价金属豆蔻酸盐(14Li,14Na,14K)和二价金属豆蔻酸盐(14Zn)分别与APAl-OH共混形成复配成核剂体系,通过熔融共混的方法添加到PP基体中制备了PP复合材料。采用差示扫描量热仪研究了复配成核剂体系对PP结晶性能的影响以及复配成核剂体系中不同金属种类的豆蔻酸盐与APAl-OH之间的协效结晶作用;采用偏光显微镜研究了复配成核剂体系细化PP球晶的能力。结果表明,当一价金属豆蔻酸盐(14Li,14Na,14K)与APAl-OH复配后,其复配成核剂体系促进PP结晶的能力随金属相对原子质量的增加而呈先上升后下降的趋势,其中14Na与APAl-OH的协效结晶作用最突出,相比于纯PP的结晶活化能(366.17 kJ/mol),PP/APAl-OH-14Na的结晶活化能下降至228.75 kJ/mol,相比于纯PP的结晶温度(110.2℃),PP/APAl-OH-14Na的结晶温度提高至126.9℃。当二价金属豆蔻酸盐(14Zn)与APAl-OH复配后,其复配成核剂体系促进PP结晶的能力不如单独添加APAl-OH,这说明14Zn与APAl-OH之间并无协效结晶的作用。

In order to study the synergistic effect of myristic acid salts with different metal and bis[2,2'-methylene-bis(4,6-di-tert-butylphenoxy)phosphoric acid]hydroxyl aluminum(APAl-OH)on the crystallization behaviors of polypropylene(PP),the compound nucleating agent systems were formed by blending monovalent metal myristic acid salts(14Li,14Na,14K)and divalent metal myristic acid salt(14Zn)with APAl-OH respectively,and the PP composites were prepared by melt blending through adding the compound nucleating agent systems into PP.The effects of the compound nucleating agent systems on the crystallization properties of PP and the synergistic crystallization between myristic acid salts with different metal and APAl-OH in the compound nucleating agent systems were studied by differential scanning calorimeter.The abilities of the compound nucleating agent systems to refine PP spherulites were studied by polarizing microscope.The results show that when the monovalent metal myristic acid salts(14Li,14Na,14K)are compounded with APAl-OH,the ability of the compound nucleating agent system to promote the crystallization of PP increases first and then decreases with the increasing of metal relative atomic mass.The synergistic crystallization of 14Na and APAl-OH is the most prominent,where the crystallization activation energy of PP/APAl-OH-14Na is decreased to 228.75 kJ/mol compared with 366.17 kJ/mol of pure PP and the crystallization temperature of PP/APAl-OH-14Na is increased to 126.9℃compared with 110.2℃of pure PP.When the divalent metal myristate(14Zn)is compounded with APAl-OH,the ability of the compound nucleating agent system to promote the crystallization of PP is not as good as that of APAl-OH alone,which indicates that there is no synergistic crystallization between 14Zn and APAl-OH on the crystallization behavior of PP.