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排序方式: 共有1091条查询结果,搜索用时 15 毫秒
101.
中国塑料助剂业发展现状及趋辨分析 总被引:1,自引:0,他引:1
综述了中国塑料助剂目前的生产、需求等行业总体状况,重点分析了增塑剂、阻燃剂、热稳定剂的现状及发展趋势,对行业发展提出一些建议。 相似文献
102.
103.
When containing extra water, soy protein concentrate (SPC) can behave like a plastic melt rather than particulate filler in blending process. In this study, blends of formulated SPC and poly(lactic acid) (PLA) were prepared. The effects of glycerol and water added to SPC on phase morphology, rheological, thermal, thermal‐dynamic, and mechanical properties of the blends were investigated. The results demonstrated that water was more effective in gelating SPC and transforming it into a plastic than glycerol. With extra water added, SPC in the resulting blend existed as stretched threads with certain degree of interconnectivity between the threads. In contrast, with only glycerol added, SPC existed as large SPC agglomerates. Consequently, the blends made from extra water‐containing SPC exhibited higher mechanical, thermal‐dynamic, and rheological properties.
104.
以不同强度等级水泥拌合的水泥净浆、水泥砂浆和水泥混凝土为原料,分别在它们中加入单一减水剂和两种混合减水剂,研究减水剂对不同水泥的适应性,以及不同品种减水剂混杂使用时的减水效果,提出了减水剂储存和使用时应该注意的问题。 相似文献
105.
106.
新型增塑剂环己烷二羧酸二烷基酯 总被引:5,自引:0,他引:5
介绍了新型增塑剂环己烷二羧酸酯的性能、制法和被其增塑的PVC制品性能评价。环己烷二羧酸酯综合性能较好,在自然环境中可降解,无生态毒性,可应用于食品包装、医疗器械和儿童玩具。 相似文献
107.
Shan Feng Pingping Jiang Pingbo Zhang Minjia Lu Zhixuan Cui Jie Pan Lingen Pan 《应用聚合物科学杂志》2023,140(3):e53331
A bio-based plasticizers, acetyl-oleate triethylene glycol (AOT), was successfully synthesized by using oleic acid as a raw material through esterification, epoxidation, and acetylation. Its structure was analyzed by Fourier transform infrared spectroscopy and 1H nuclear magnetic resonance. The plasticizing performances of this plasticizer was compared with those of two commercial ones: dioctyl terephthalate (DOTP) and dioctyl adipate (DOA). This was done by blending these plasticizers with PVC, respectively. Thermal gravimetric analysis results showed that the 5% weight loss temperature of PVC with AOT was 53°C higher than that of DOA and 36°C higher than that of DOTP. The tensile results showed that the AOT plasticized PVC had excellent stretchability: its elongation at break with 50 phr AOT reached 697.7%. Furthermore, its transmittance was as high as 90%, showing better compatibility of ATO with PVC. 相似文献
108.
Turning brittle poly(lactic acid) (PLA) to ductile form via plasticizer inclusion is an effective option in the case of processing with high amounts of additives. Additionally, the integration of natural flame retardants to PLA involving bio-based plasticizer enables to use of environmentally friendly composites in conditions where fire resistance performance is required. In the current study, ductile green fire retardant PLA composites were manufactured using hydromagnesite&huntite (HH) as a natural fire retardant additive and acetyl tributyl citrate as a bio-based plasticizer. The influences of plasticizer and HH contents on the fire retardant, thermal and mechanical performances of the composites were explored. According to test results, the limiting oxygen index (LOI) value of PLA reduced from 29.2 to 28.0 and the UL-94 V rating changed from V2 to BC with the addition of 20 wt% plasticizer owing to the reduction in melt viscosity. The peak heat release rate (pHRR) and average heat release rate (avHRR) values increased steadily as the concentration of plasticizer increased due to the formation of a more porous residue structure stemming from the increased transportation rate of gases. In order to produce ductile flame retardant material, the plasticizer content was required to 20 wt% of HH. The highest LOI value (36.2) and UL-94 rating of V0 were achieved with the inclusion of 70 wt% HH in the presence of 20 wt% plasticizer. Improvement in impact resistance and reduction in tensile strength were observed as the added amount of plasticizer increased. 相似文献
109.
Dilyara F. Sadykova Nikita Yu. Budylin Uliana V. Nikulova Aleksey V. Shapagin Elena M. Gotlib 《应用聚合物科学杂志》2024,141(1):e54748
The influence of rice hull ash and wollastonite on the migration problem of plasticizer EDOS from polyvinyl chloride (PVC) has been studied. The methods of optical interferometry, IR spectroscopy, viscometry, SEM and EDX were used to study the mutual solubility and diffusion mobility in the PVC-EDOS system in the presence fillers and without them, as well as the phase structure of plasticized filled systems. It is shown that in a fully compatible PVC-EDOS system, a diffusion mixing mechanism is observed, and the interdiffusion coefficients increase from 10−8 to 10−6 (cm2/s) with increasing plasticizer concentration. The introduction of a dispersed filler somewhat reduces the interdiffusion coefficients. The sorption of the plasticizer on the surface of the dispersed filler has been established, which leads to a decrease in the migration of EDOS from the composition. It was found that the introduction of wollastonite leads to a smaller increase in viscosity and an improvement in the technological properties of the system. And the introduction of environmentally neutral rice husk ash reduces the migration of the plasticizer and improves the stability of the composition during operation, which also has a positive effect on the environmental friendliness of this system. 相似文献
110.
尼丝纺、涤丝纺和牛津纺采用聚氯乙烯涂层,具有与天然皮膜接近的外观和触觉,是当前经济价值较高的产品,文中简述了聚氯乙烯涂层的具体生产工艺及应注意的事项。 相似文献