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研究了滴灌带用聚乙烯(PE)混配料中加入抗氧剂,经多次挤出后产物的熔体流动速率、羰基指数及拉伸性能的变化,分析了抗氧剂对回收滴灌带用PE热氧老化性能的影响。结果表明:加入抗氧剂可降低滴灌带用PE的热氧化反应速率;添加抗氧剂比未添加抗氧剂的PE微观化学性能和宏观力学性能都有明显提高。 相似文献
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回收高密度聚乙烯结构与性能的研究 总被引:2,自引:0,他引:2
袁聪慧;王仕峰;张勇;张隐西 《中国塑料》2011,25(10):81-85
采用傅里叶变换红外光谱仪、差示扫描量热仪和热重分析仪分析了市售回收高密度聚乙烯(PE-HD)的结构特点,并对其熔体流动性和力学性能进行了研究。结果表明,在回收再利用过程中,PE-HD的结构发生了明显的变化,产生了羰基,其老化程度越大,产生的杂峰越多。回收PE-HD的熔融流动性较差,力学性能也有不同程度的下降。根据拉伸强度的大小,回收PE-HD可分为一级料、二级料和三级料。 相似文献
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通过人工加速光老化与自然气候暴露老化试验,运用拉伸实验手段对老化前后内镶式滴灌带的力学性能进行表征,并用红外光谱对其结构变化进行分析,研究抗老化母粒对滴灌带耐老化性能的影响。结果表明,人工老化12 d和自然暴露老化120 d与未老化试样相比,断裂伸长率保持率添加自制抗老化母粒的分别为84.7 %、83.2 %,未添加抗老化母粒的分别为59.8 %、58.2 %;未添加抗老化母粒的试样在1723 cm-1处生成的羰基峰明显较强,配方中添加自制抗老化母粒起到了抗紫外的作用。 相似文献
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以回收聚乙烯(PE)地膜为载体,先用单因素实验筛选出抗氧剂和光稳定剂的最佳种类,再利用正交实验筛选出滴灌带防老化母料各助剂的配比,并对以回收PE地膜为载体的防老化母料进行性能研究。受阻酚1076的抗氧强度提升最高,氧化诱导时间为5.19 min,经过16 d热氧老化后,断裂伸长率保持比为79.6%,冲击强度保持比为74.9%,老化后材料C—O键连接方式占2.01%、C=O键连接方式占0.5%,且熔体质量流动速率随热氧老化变化呈上下波动。光稳定剂GW622、GW944、UV531的耐紫外线稳定性良好,经28 d紫外线老化后断裂伸长率保持率高达94.0%,拉伸强度一直保持在5.05 M Pa。经3因素3水平9组正交试验结果得出:10%GW622与GW944、15%UV531、20%受阻酚1076为最佳滴灌带防老化母料配比。添加自制防老化母料制备滴灌带,滴灌带热稳定性明显提升,Tonset和Tmax分别为445℃、477.7℃。红外分析1 350 cm-1和1 650 cm-1处峰值较弱,28 d紫外老化... 相似文献
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针对退役汽车保险杠老化后的性能提升问题,采用熔融共混改性法研究了三元乙丙橡胶(EPDM)、乙烯–辛烯共聚物(POE)两种弹性体,碳酸钙、滑石粉和纳米蒙脱土(nano-MMT)三种无机填料对退役汽车保险杠回收料性能的影响。结果表明:弹性体的加入能够显著增强回收料的韧性,对回收料的刚度有一定程度的影响,也能一定程度提高回收料的流动性;POE改性回收料的综合性能优于EPDM改性的回收料,在POE含量为10%时回收料的综合性能最优,拉伸强度为21.2 MPa,断裂伸长率为201.5%,弯曲强度为17.6 MPa,缺口冲击强度为56.3 kJ/m~2,熔体流动速率为12.4 g/10 min;无机填料改性回收料的综合性能表现较差,加入相容剂能够显著提升无机填料共混体系的综合性能,nano-MMT对回收料的改性效果优于另外两种无机填料。 相似文献
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乙烯酮(双乙烯酮)是十分重要的化工中间体,其下游产品较多。江苏某化工厂开发生产乙烯酮(双乙烯酮)下游产品三十多个,年生产规模三万多吨,是国内以乙烯酮(双乙烯酮)为中间体生产精细化学品的综合骨干企业。针对乙烯酮(双乙烯酮)下游产品废水特点,该厂结合企业实际,开展了产品优化,结构调整,清洁生产,资源循环利用,节水降耗等工作,从源头削减了污染物的生产。同时投资二千多万元新建预处理装置三套,6000m3/d废水生化处理装置一套,使全厂乙烯酮(双乙烯酮)下游产品的废水得到了有效的治理。 相似文献
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D. G. Gordeev L. F. Gudarenko M. V. Zhernokletov V. G. Kudel’kin M. A. Mochalov 《Combustion, Explosion, and Shock Waves》2008,44(2):177-189
A semi-empirical equation of state for metals is described. Its capabilities are demonstrated by the example of the equation
of state for aluminum. New experimental data are presented on the location of the isentrope of aluminum for unloading from
the state at p = 229.71 GPa on the shock adiabat to an aerogel (SiO2) of density 0.08 g/cm3.
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Translated from Fizika Goreniya i Vzryva, Vol. 44, No. 2, pp. 61–75, March–April, 2008. 相似文献
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Jorge Marcelo Romero Soledad Bustillo Hugo Enrique Ramirez Maisuls Nelly Lidia Jorge Manuel Eduardo Gómez Vara Eduardo Alberto Castro Alicia H. Jubert 《International journal of molecular sciences》2007,8(7):688-694
A thermochemical rather simple experimental technique is applied to determine the enthalpy of formation of Diperoxide of ciclohexanone. The study is complemented with suitable theoretical calculations at the semiempirical and ab initio levels. A particular satisfactory agreement between both ways is found for the ab initio calculation at the 6–311G basis This set level. Some possible extensions of the present procedure are pointed out. 相似文献
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The objective of the study was to explore the effect of the degree of deacetylation (DD) of the chitosan used on the degradation rate and rate constant during ultrasonic degradation. Chitin was extracted from red shrimp process waste. Four different DD chitosans were prepared from chitin by alkali deacetylation. Those chitosans were degraded by ultrasonic radiation to different molecular weights. Changes of the molecular weight were determined by light scattering, and data of molecular weight changes were used to calculate the degradation rate and rate constant. The results were as follows: The molecular weight of chitosans decreased with an increasing ultrasonication time. The curves of the molecular weight versus the ultrasonication time were broken at 1‐h treatment. The degradation rate and rate constant of sonolysis decreased with an increasing ultrasonication time. This may be because the chances of being attacked by the cavitation energy increased with an increasing molecular weight species and may be because smaller molecular weight species have shorter relaxation times and, thus, can alleviate the sonication stress easier. However, the degradation rate and rate constant of sonolysis increased with an increasing DD of the chitosan used. This may be because the flexibilitier molecules of higher DD chitosans are more susceptible to the shear force of elongation flow generated by the cavitation field or due to the bond energy difference of acetamido and β‐1,4‐glucoside linkage or hydrogen bonds. Breakage of the β‐1,4‐glucoside linkage will result in lower molecular weight and an increasing reaction rate and rate constant. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3526–3531, 2003 相似文献