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With the rapid development of the packaging industry, waste poly (ethylene terephthalate) beverage bottles has become one of the main ingredients that constitute the city's solid waste. Recycled polyethylene terephthalate (R-PET) bottles due to higher economic, resource and environmental values ??by more and more attention. However, R-PET used in the processing, recovered, and then processing the part of the molecule may occur pyrolysis, hydrolysis, thermal mechanical, and biological degradation reaction, resulting in the melt strength and the intrinsic viscosity reduced, and thus can not meet the spun filaments and blowing and other direct reprocessing requirements. The same time due to the decrease in molecular weight, degree of crystallinity increased, the brittleness of the material is increased, the toughness is reduced, it is difficult to meet the requirements of the engineering plastics with high mechanical properties. Indeed, polyethylene terephthalate glycol esters (PET), due to the presence of the slow crystallization rate, product shrinkage, poor dimensional stability disadvantages, also subject to considerable restrictions on the applications as injection molding of engineering plastics. This article from the chain extender, toughening and crystallization of R-PET, PET and its composite materials were studied. Having a polyfunctional straight-chain epoxy structure ADR4370S chain extender, on a torque rheometer, using situ molten chain extender method modified R-PET, and by the dynamic rheological DSC, torque Rheological analysis studied by means of chain extender modified condition parameters of R-PET molecular weight, molecular chain structure, a sol-gel transformation, the thermal influence of the mechanical stability and the like. Experimental results show that the With increase in ADR4370S addition amount, the molecular weight of the modified R-PET increases, the molecular weight distribution broadens, the increase in the degree of branching of the molecular chain, the intrinsic viscosity and the melt strength is increased; When the amount of chain extender 0.5 wt%, the characteristics of the modified R-PET viscosity from 0.59 dL / g increases to 0.61dL / g, close to the original raw material BG80 (0.62 dL / g) standard; When the amount of the chain extender is 1.5 wt%, the system appears to the sol-gel conversion; an amount of 2.0 wt%, the system appeared in the gel structure. The results also show that the modified R-PET thermo-mechanical stability and crystallization rate showed a downward trend. R-PET, on a torque rheometer using the amorphous ternary block copolymer ABS and partially crystalline melt banburying the prepared R-PET/ABS blend. One-step melt mixing the preparation of graft rate of approximately 5% of the ABS-g-MAH copolymer, with its the compatibilizer R-PET/ABS blend system performance prepared R-PET/ABS/ABS-g -MAH alloys. And DSC, SEM, DMA, rotational rheometer, characterized, and analyzed the relationship between the structure and composition of the phase morphology of the R-PET/ABS alloy mass ratio, viscosity rate and the compatibilizing agent content. Experimental results show that: R-PET/ABS partially compatible system, but to add an appropriate amount of ABS-g-MAH, can significantly improve the compatibility of the blend, in the ABS-g-MAH compatibilization R-PET / the ABS blends the ABS component content is increased, the phase structure of the blends by the island structure gradually to some co-continuous two-phase coexistence shift; while the the fixed component mass ratio change components sticky rate, you can change two-phase interfacial area and phase morphology. The a select lanthanum complex objects (LAC) heterogeneous nucleating agent, as PET the torque rheometer molten banburying PET / LAC composites were prepared. Take the means of DSC, POM, XRD and rotation rheological analysis, to characterize PET / LaC isothermal and non-isothermal crystallization kinetics of the process as well as PET crystal morphology changes. Experimental results show that: LAC to improve the crystallization rate of the PET non-isothermal, refinement of the crystal form and to shorten the crystallization cycle, the addition amount of 0.85 wt%, the best results; as the Lac added amount increases, the system of the storage modulus and loss modulus first decreased and then increased Newtonian flow properties of the melt increases, the glass transition temperature of the processing energy consumption of the system and PET decreased.
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