| With the rapid development of technology, many single polymer materials can't meet the more and more stringent requirements. Since the polymer alloy materials has excellent overall performance, light weight and low cost, it has become a hot research subject.Polymer blending modification has already been proved to be an effective means of improving the mechanical properties of engineering plastics. However, because of the polymer thermodynamic, most of the blend compatibility among the various components is not good. As a result, functionalized polymer with a special structure is widely used as a phase compatibilizer to improve the interaction force between phases of each component, and ultimately improve the performance of engineering plastics. In a previous study we found that enhanced radiation can also improve the blends force. Basing on this theory ,we significantly enhanced the aromatic polyester terephthalate (PET) of the mechanical properties by using non-functionalized elastomeric ethylene-octene copolymer (POE). Can enhanced radiation and functional group response then be cooperate with each other and conjointly improve the interphase force of the incompatible blends, thus ultimately coming to the preparation of high-performance engineering materials? This is the main issue to study in the dissertation.This paper uses different functional groups of PET blending with POE to achieve the two kinds of ternary alloys, PET/POE-g-MAH/C and PET/POE-g-GMA/C, and strengthens the materials with enhanced radiation. Mechanical testing, gel extraction and scanning electron microscopy are used to characterize the radiation effects of the blends. The interaction of enhanced radiation and functional group response in the interface compatibilization and toughening aspects is studied, and the radiation effects are compared among the different functionalized POE blends. Finally, the thesis of this study has extended to the biodegradable aliphatic polyester - polylactic acid (PLA) of the blend system, and has achieved the ternary alloy of PLA/POE-g-MAH/A. And through the relevant test we studied the interaction of enhanced radiation and functional group response in the interface compatibilizer, as well as composite compatibilizer on the mechanical properties of PLA.The results show that the compatibility of the blends improved significantly as during the process of melt blending the functional group of the functionalized POE and PET functional groups on the base react with each other. Comparison of scanning electron microscopy (SEM) images found PET / POE blends have smooth and flat impact fractures. While PET/POE blends own uneven ones, with a certain degree of plastic deformation. Compared with PET/POE-g-GMA and PET/POE-g-MAH we can see that POE-g-GMA toughened PET blends have larger elastomer particle size than PET / POE-g-MAH, then it can be figured out the interface compatibilizer of POE-g-MAH is superior to that of POE-g-GMA. When irradiating the two systems, PET / POE-g-MAH system shows strong resistance to irradiation, while the other system is significantly affected by radiation. After receiving the 30kGy radiation, the 20wt% POE-g-GMA blends produced more plastic deformation in the fracture process. This shows that the GMA functional groups and radiation can simultaneously increase capacity on PET / POE.Radiation to the ternary blends of PET / POE-g-MAH / C can't improve the performance of PET / POE-g-MAH. The maximum impact strength 13.7 KJ/m2 is only1.4 KJ/m2larger than that of no crosslinking C. This may be due to the low radiation response activity among the POE-g-MAH,PET and C, thus MAH functional groups and enhanced radiation do not achieve the synergies and strengthen the capacity.Radiation to the ternary blends of PET/POE-g-GMA/C significantly improved the compatibility of PET/POE-g-GMA and the interphase force of the blend components. Mechanical test results show that the addition of crosslinking agent C and radiation can be effectively compatibilizing and toughening to the blends. Radiation dose and C content have little effect on the mechanical properties of the blends whose content of POE-g-GMA is less than 10wt%.This may be due to the small interfacial area and interface spacing of the blend components with low elastomer content. The impact strength of ternary blends with 15wt% POE-g-GMA increases with the dose of radiation first and then decreases. Blends with 3wt% C appear brittle-ductile transition in the range of 10 ~ 30kGy of the radiation dose.Ternary blends with 20wt% POE-g-GMA have great impact strength, and it increases slightly with the increase in radiation dose. Blends with 0.5wt% C have the best impact strength. The reason may be that it can gain the best compatibilizer when cross-linking agent molecules of the blend interface present as a single molecular layer. As the radiation dose increases, the tensile strength of ternary blends first increases and then decreases. Elongation at break and Young's modulus changed little overall. Blends whose C content is of less than 1wt% have better overall performance. The optimum ratio of PET/ POE-g-GMA/C is 80/20/0.5(wt/wt/wt),and the optimal radiation dose is 5kGy. Impact strength of blends is10 times more than that of pure PET, and tensile strength is 61.8%of pure PET. Compared with the SEM pictures of impact fracture before and after adding crosslinking agent C blends, it will be found elastomer particle size of ternary blends decreases. After radiation, interfacial bond strength of blends increased significantly, and the two phases show apparent plastic deformation during the fracture process. This indicates enhanced radiation and functional group response have a synergistic effect in the interface compatibilizer. Gel extraction results show that the main reason for the synergy and compatibilizer of enhanced radiation and functional group response may probably be thegraft reaction of the blends at the interface.Comparing with the three blends of PET/POE/C,PET/POE-g-MAH/C and PET/POE-g-GMA/C, it can be concluded that the capacity of enhanced radiation and compatibilizer of the three elastomers is POE-g-GMA> POE> POE-g-MAH orderly. Enhanced radiation is closely related to the blends'compatibilizer and the type of functional group.The radiation effects studies of the PLA / POE-g-MAH / A shows that enhanced radiation and functional group response have a synergistic effect in the interface compatibilizer of the PLA blends. Mechanical test results show that as the radiation dose increased, the impact strength of ternary blends first increases and then decreases, and blends with high crosslinker content have better impact strength. The impact strength of blends with less than 30% POE-g-MAH content doesn't change significantly with the increase of radiation dose. This may be due to the small interfacial area and interface spacing among the components of the blends with low elastomer content and the low activity of PLA. The tensile strength of blends with less than 1% A doesn't change significantly as the radiation dose increases, while that of blends with more than 1% A has a certain increase. Young's modulus of the blends and the elongation first increase and then decrease as the radiation dose increases. The optimum ratio of PLA/POE-g-MAH/A is 50/50/3(wt/wt/wt),and the optimal radiation dose is 30kGy. Impact strength of blends is 4 times more than that of pure PLA. SEM photographs of the impact fracture show that after irradiation, the interface bond strength of the blends increases, and clear plastic deformation occurs during the fracture process. Gel extraction results show that the main reason for the synergy and compatibilizer of enhanced radiation and functional group response may probably be the graft reaction of the blends at the interface.Elastomer mixing with polyester can improve its impact strength. At the same time the drop in tensile properties can't be avoided. Blends synergistic by enhanced radiation and functional group response can slightly increase of the tensile properties of the blends.
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