【摘要】 通过甲基丙烯酸缩水甘油酯(GMA)、聚乙烯(PE)、木粉和其它助剂的熔融挤出,实现了GMA及GMA与共单体对PE和木粉的直接反应增容.通过扫描电镜(SEM)观测了PE基木塑复合材料(WPC)的冲击断面形貌.测试了WPC经抽提后所得木粉的傅立叶变换红外光谱(FTIR)和WPC的力学性能及热变形温度(HDT).研究了共单体苯乙烯(St)和抑交联剂亚磷酸三苯酯(TPP)对反应增容的影响.结果显示,经GMA和引发剂反应增容后,有部分PE分子键合到了木粉粒子上,从而增强了木塑两相的结合力;St的加入有利于提高GMA的接枝率,导致更多PE分子键合到了木粉粒子上,而TPP的加入则使GMA的接枝率有所下降.经GMA和引发剂直接反应增容后,WPC的力学性能和HDT均明显改善;St的加入有助于抑制PE的交联,但并未造成WPC力学性能和HDT的明显劣化;同时加入St和TPP后,WPC的HDT有所下降,而断裂伸长率和冲击强度则明显提高.更多还原

【Abstract】 Compatibilization between polyethylene(PE) and wood-flour was achieved by means of direct reactive extrusion of glycidyl methacrylate(GMA),PE,wood-flour and other additives.Impact cracking surfaces of the PE/wood-flour composites(WPCs) were observed via scanning electron microscope(SEM).Fourier transform infrared(FTIR) spectra of wood-flour extracted from the WPCs were measured.Heat distortion temperatures(HDTs) and mechanical properties of the WPCs were tested.The effect of comonomer styrene(St) and anti-crosslinking agent triphenyl phosphite(TPP) on the reactive compatibilization was also evaluated.Experimental results indicated that some of PE chains in the WPCs were bonded onto the surface of wood-flour after reactive extrusion resulting in the improvement of compatibility between PE and wood-flour.Both increased grafting ratio of GMA,and more bonded PE chains on the surface of wood-flour were evidenced due to the addition of St.However,the addition of TPP reduced the grafting ratio of GMA.Mechanical properties and HDTs of the WPCs were obviously improved after direct reactive extrusion.At 1.5 wt% of GMA and 0.3 wt% of DCP in the extrusion composition of WPC,the tensile strength,flexural strength,elongation at break,notched impact strength and HDT of WPC respectively increased by 67%,23%,32%,43% and 7.7 K comparing to those of the WPC without reactive extrusion.The addition of St was able to inhibit the cross linking reaction of PE,however,there was no significant changes observed for its mechanical properties and HDT.When both St and TPP were added in the WPC,the composites’ HDT decreased while elongation at break and notched impact strength were improved.更多还原