Study On The Application Of EPDM-g-MAH Improving Toughness Of Polymeric Matrix/Nonmetals Recycled From Waste PCB Composites

In this thesis, EPDM-g-MAH were prepared by reaction extrusion moulding, and then it was blended with nonmetals recycled from waste PCB(N-PCB) and high density polyethylene (HDPE) or polypropylene (PP) to prepare composites. The toughening efficiency of EPDM-g-MAH were studied.The grafting ratio of EPDM-g-MAH were characterized by drawing IR calibration curve. The factors affecting the melt grafting was investigated and the results indicated that the best technical parameters should be:the temperature:200℃; the reaction time:4min; the MAH dosage:2phr; the St dosage:2phr; the DCP dosage:0.1phr. The grafting ratio of EPDM-g-MAH reached above1.28%under these conditionsThe effect of EPDM-g-MAH on toughening HDPE/N-PCB matrix were studied. SEM and FT-IR analysis results indicated that MAH grafted onto EPDM could significantly improve the compatibility between EPDM and N-PCB, EPDM-g-MAH had better toughening effect than EPDM. The research on mechanical performance of the HDPE/N-PCB/EPDM-g-MAH composites showed that the N-PCB powder particle size was120-160mesh and the master batch was extruded by twice, the composites(wt:HDPE/N-PCB/EPDM-g-MAH=100:40:15) has the best comprehensive properties. The increment of notched impact strength and elongation at break of the HDPE/N-PCB/EPDM-g-MAH composites is458%and459%, compared to the HDPE/N-PCB matrix, but tensile strength, flexural strength and modulus of elasticity decreased. And when compared to HDPE/N-PCB/EPDM composites, the increment of notched impact strength is38%, there is no significant difference in tensile strength, flexural strength, elongation at break and modulus of elasticity performance.The effect of EPDM-g-MAH on toughening PP/N-PCB matrix were studied. SEM and FT-IR analysis results indicated that MAH grafted onto EPDM could significantly improve the compatibility between EPDM and N-PCB, EPDM-g-MAH had better toughening effect than EPDM. The research on mechanical performance of the PP/N-PCB/EPDM-g-MAH composites showed that the N-PCB powder particle size was120-160mesh and the master batch was extruded by twice, the composites(wt: HDPE/N-PCB/EPDM-g-MAH=100:40:15) has the best comprehensive properties. The increment of notched impact strength and elongation at break of the HDPE/N-PCB/EPDM-g-MAH composites is157%and309%, compared to the HDPE/N-PCB matrix, but tensile strength, flexural strength and modulus of elasticity decreased. And when compared to HDPE/N-PCB/EPDM composites, the increment of notched impact strength is14%, there is no significant difference in tensile strength, flexural strength, elongation at break and modulus of elasticity performance.All the results indicate that the effect of EPDM-g-MAH on toughening HDPE/N-PCB and PP/N-PCB matrix were obvious. The notched impact strength and elongation at break of HDPE/N-PCB and PP/N-PCB matrix can effectively improve by adding EPDM-g-MAH, which provides a new method for recycling of N-PCB.