Study On The Properties Of Polymer Composities Under The Behavior Of Multiple Fracture

PA6 is one kind of important thermoplasitc and which is used in automobile, electrical equipment and mechanical fields. PA6 shows an obvious shortcoming that is notch sensitivety and lower notched impact strength at room temperature. Core-shell modifier can be prepared with controled structure,steady particle size and higher toughening efficiency and which has been used as toughener of PA6. In the present article,acrylonitrile-butadiene-styrene copolymer (ABS) was used as toughener of PA6. The core phase is polybutadiene and the shell phase is acrylonitrile-styrene copolymer for ABS. The major researches were as follows:1.PA6/ABS0215A blends were prepared and a third polymer as compatibilizers was used to improve properties of the blends. The result confirmed that compatibilizer SAM302 improved the performance of the copolymer and enhanced the toughness remarkablely compared to copolymers materials made from other compatibilizers. The blends displayed excellent disperse morphology.2.A series of ABS impact modifiers were synthesized by grafting styrene and acrylonitrile onto PB particles with the different type of initiators (AIBN or CHP) and blended with PA6/SAM302. The amine end groups of PA6 and the anhydride groups of SAM react with each other during melt blending; This leads to the formation of a comblike graft copolymer at the interface between PA6 and SAM. Mechanical properties tests showed that ABS prepared with CHP as initiator displays much better toughening effect.3.ABS with different crosslinking degree by varied DVB content were prepared and which were used to toughen PA6. Results showed the toughness of blends do not affect obviously when the test was carried out at room temperature.however, the toughness decreases significantly at the lower temperature. The crosslinking does not change the disperse morphology of ABS in the PA6 matrix and which dispersed in PA6 uniformly.4.Acrylonitrile-Butadiene-Styrene (ABS) core-shell particles grafted maleic anhydride with different sizes were synthesized via emulsion polymerization,which was employed to blend with PA6 via melt mixing. The mechanical properties of PA6/ABS-MA blends were investigated. Larger particles size of ABS-g-MA resulted in higher tensile strength and appear brittle-ductile transition. ABS with small particles showed poor toughening effect on PA6.5.ABS-g-MA copolymers were used to toughen PA6 and the mechanical properties were compared with PA6/ABS/SAM302 blends. The results showed PA6/ABS-g-MA blends displayed much better mechanical properties than the PA6/ABS/SAM302 blends.