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1.
Konstantin V. Pochivalov Alexander N. Shilov Tatyana N. Lebedeva Anna N. Ilyasova Roman Yu. Golovanov Andrey V. Basko Yaroslav V. Kudryavtsev 《应用聚合物科学杂志》2021,138(15):50196
A detailed study of butyl rubber-based vibration damping formulations linking their composition, morphology, phase structure, viscosity, mechanical loss factor, and other characteristics is presented for the first time. High performance of the compositions including aromatic petroleum oil is explained by limited solubility of the plasticizer that leads to the formation of a highly-viscous emulsion (η20°C ≈ 1000 Pa·s) consisting of a swollen butyl rubber matrix and dispersed oil droplets in the broad composition range. Chalk is found to be the best inorganic filler as its spherical particles provide strong adhesion to the reinforcing layer of aluminum foil. Aiming to eliminate ecologically unfriendly aromatic compounds, a new low-cost binding agent formulation based on butyl rubber mixed with polyisobutylene and highly refined mineral oil is suggested. Being environmentally safe, it possesses high viscosity of 1000–3000 Pa·s, cohesion strength of 3.5–5.0 N/cm, penetration of 4.5–6.0 mm, and mechanical loss factor up to 0.34 at room temperature, which are as good as, or even better than, the properties of currently produced vibration damping materials containing aromatic compounds. New materials can be used in car and aircraft parts for effective vibration isolation. 相似文献
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The effect of three additives derived from pine resin, namely, gum rosin (GR) and two pentaerythritol ester of GR, Lurefor (LF) and Unik Tack (UT), in 5, 10, and 15 wt %, on the properties of Mater-Bi, based on plasticized starch, poly(butylene adipate-co-terephthalate), and poly(ε-caprolactone) (PCL), obtained by injection molding processes, was studied. The mechanical, microstructural, and thermal properties were evaluated. LF had a cohesive behavior with the components of Mater-Bi, increasing the toughness of the material up to 250% accompanied by an increase of tensile modulus and tensile strength. UT had an intermediate behavior, conferring cohesive and plasticizing effects, allowing an increase of 105% in impact resistance. GR had a more marked plasticizing effect. This allows processing temperatures of about 50 °C lower than those used for neat Mater-Bi. In addition, an increase of the elongation at break, toughness, and impact resistance in 370, 480, and 250%, respectively, was achieved. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48236. 相似文献
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通过掺加不同含量糠醛抽出油、红油增塑剂与苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS)改性剂,分析其对SBS改性沥青各性能指标的影响,判断影响SBS改性沥青性能的主要因素。结果表明:改性沥青中SBS改性剂含量是提高软化点、弹性恢复的主要因素;糠醛抽出油含量增大则可明显提高其延度指标,且改善SBS改性沥青的离析程度;红油增塑剂含量增大可大幅提高SBS改性沥青的延度指标,但高温性能下降且离析严重,短期老化后指标下降幅度高于同等含量抽出油老化后指标。因此可在SBS含量确定的情况下,通过掺加适当的糠醛抽出油以改善SBS改性沥青的性能。 相似文献
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3,4-二(3-氟偕二硝基-4-氧)呋咱: 一种新型热稳定高能量密度增塑剂(英) 总被引:1,自引:1,他引:0
自行设计并合成了一种含有氟偕二硝基的新型高能增塑剂3,4-二(3-氟偕二硝基-4-氧)呋咱.通过FT-IR、13C NMR、19F NMR、元素分析、DSC等分析手段进行了结构表征.基于计算的标准生成焓以及实测的密度,采用Kamlet-Jacobs方程计算了3,4-二(3-氟偕二硝基-4-氧)呋咱的爆轰性能,并与常用增塑剂:硝化甘油(NG)和二(氟偕二硝基)甲醛(FEFO)和3,3'-二硝基双呋咱醚(FOF-1)的爆轰性能进行了对比.结果表明,3,4-二(氟偕二硝基-4-氧)呋咱具有热稳性好(分解温度197.8℃)、密度大(1.88 g·cm-3)、熔点低(50℃)和能量水平高等特点,是一种综合性能优异的含能增塑剂. 相似文献
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增塑剂对纤维素膜表面结构和性能的影响 总被引:3,自引:3,他引:0
天然纤维素膜不经任何处理直接干燥,膜发脆、卷曲,作用不大.采用甘油做增塑剂来改变纤维素膜的柔顺性,研究了不同的增塑条件对纤维素膜表面结构和性能的影响及甘油的塑化机理.通过力学性能测试、表面形态的观察及红外光谱分析,研究表明,甘油在一定程度上改变了纤维素膜的柔顺性,但同时却使纤维素膜的力学性能变差,并且增塑的膜经水洗后,甘油易流失,增塑效果减弱. 相似文献
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HTPE/增塑剂共混体系相容性的分子动力学模拟 总被引:1,自引:1,他引:0
用分子动力学(MD)方法模拟研究了粘结剂端羟基聚醚(HTPE)与增塑剂邻苯二甲酸二丁酯(DBP),癸二酸二辛酯(DOS)和邻苯二甲酸二乙酯(DEP)的相容性及HTPE/增塑剂共混物的玻璃化转变温度(Tg)。结果表明,当共混体系中存在较强的分子间氢键作用时,通过分析结合能、径向分布函数和玻璃化转变温度,可综合评价HTPE与增塑剂的相容性。HTPE与三种增塑剂相容性的优劣顺序为HTPE/DBPHTPE/DOSHTPE/DEP;通过温度-比容关系得到了HTPE,HTPE/DBP,HTPE/DOS及HTPE/DEP四种体系的Tg,依次为190.26,176.30,168.82,178.33 K。 相似文献
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Improvement of processing and mechanical properties of polyetherimide by antiplasticization with resorcinol bis(diphenyl phosphate) 下载免费PDF全文
This article describes the antiplasticization of a commercial polyetherimide ULTEM® series 1000 [poly(bisphenol A‐co‐4‐nitrophthalic anhydride‐co‐1,3‐phenylenediamine) by resorcinol bis(diphenyl phosphate)] (RDP) and its implications on the thermomechanical processing, namely extrusion and injection molding, as well as on the thermal and mechanical properties of the formulations. This antiplasticization effect allows the processing of polyetherimide formulations at lower temperatures in comparison with neat polymer due to the progressive decrease of the glass transition temperature with increased RDP concentration, as observed by differential scanning calorimetry and dynamic mechanical analysis. The decrease of Tg occurs concomitantly with the overlap of the glass transition and β relaxation and with the shift of the γ relaxation to higher temperatures. These changes in the relaxation spectrum of polyetherimide formulations are possibly responsible for the increase of the tensile strength and Young's modulus and changes in the fracture mechanism, as observed by stress–strain tests and by scanning electron microscopy, respectively. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40619. 相似文献