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熔融行为

熔融行为的相关文献在1993年到2020年内共计102篇,主要集中在化学工业、化学、一般工业技术 等领域,其中期刊论文85篇、会议论文17篇、专利文献39450篇;相关期刊36种,包括天津工业大学学报、功能材料、石油化工等; 相关会议14种,包括2015年中国工程塑料复合材料技术研讨会、2014年中国地球科学联合学术年会、2013年全国岩石学与地球动力学研讨会等;熔融行为的相关文献由317位作者贡献,包括麦堪成、李亚东、曾汉民等。

熔融行为—发文量

期刊论文>

论文:85 占比:0.21%

会议论文>

论文:17 占比:0.04%

专利文献>

论文:39450 占比:99.74%

总计:39552篇

熔融行为—发文趋势图

熔融行为

-研究学者

  • 麦堪成
  • 李亚东
  • 曾汉民
  • 薛美玲
  • 张治军
  • 张跃飞
  • 强克刚
  • 蔡艳华
  • 方少明
  • 李政军
  • 期刊论文
  • 会议论文
  • 专利文献

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    • 侯丽强; 朱大欢; 吴清; 刘一泽; 刘兆东; 郑洪涛
    • 摘要: 为支撑堆芯熔融物压力容器内滞留有效性评估,采用计算流体动力学方法,建立了某先进压水堆堆芯辐射传热数值模型,对严重事故下围板及吊篮的熔融行为及其影响因素进行了研究.研究结果表明,在靠近堆芯燃料组件轴向功率分布因子峰值的节点,围板及吊篮的熔融行为较为显著;在同一节点处,围板的熔融并不是均衡发展的,最先熔穿的区域多发生在外围多个燃料组件交汇处,而吊篮的熔融则呈现出由内向外均衡扩展的变化趋势;压力容器外壁面的换热条件对堆芯围板及吊篮的熔融行为的影响并不显著,而燃料组件发射率的设置对堆芯围板及吊篮的熔融行为具有显著影响.可以为堆芯熔融物压力容器内滞留有效性评估提供技术支持.
    • 余兰兰; 邢士龙; 郑凯; 刘红波
    • 摘要: 为进一步认识半结晶型聚合物性能与结构的关系,以苯丙二酸钙作为聚L-乳酸的结晶促进剂,借助差示扫描量热仪、热失重分析仪、熔融指数仪和透光仪考察其改性聚L-乳酸材料的结晶行为、熔融行为、热稳定性、流动性以及透光性等物理性能.非等温结晶测试结果显示,苯丙二酸钙可显著加速聚L-乳酸的结晶过程,其中5%的苯丙二酸钙可使聚L-乳酸具有最大的非等温结晶焓,且结晶可以在更高温度下发生;同时降温速率以及非等温结晶方式都会对聚L-乳酸的非等温结晶过程产生显著影响.不同条件下熔融行为的差异进一步证实了苯丙二酸钙对聚L-乳酸的结晶促进作用,另外熔融行为也依赖于结晶温度.相关测试进一步表明,苯丙二酸钙会降低聚L-乳酸的热稳定性和透光性,但会大幅提高聚L-乳酸的加工流动性.
    • 王树杰; 吕康辉; 刘英杰; 高晟强; 薛美玲
    • 摘要: 通过调节聚偏氯乙烯涂覆膜固化时的温度梯度和时间梯度,研究了成膜过程中温度制度和时间制度对其结晶性能的影响.结果表明:固化温度为60°C时,链段运动较难,结晶能力差,结晶行为明显依赖于固化时间.升温过程中冷结晶峰显著,表明结晶不充分,70°C时,冷结晶峰依然存在;80~85°C时,5 min左右可形成完善结晶,冷结晶峰消失,且主熔融峰焓高于固化温度为60~70°C时的,结晶行为理想.
    • 林祥凤; 刘抱; 张跃飞
    • 摘要: Three types of calcium pimelate,D-CaPi,N-CaPi and S-CaPi,were prepared by a metadecomposition reaction,a neutralization reaction and physical compounding of pimelic acid with calcium stearate,respectively,and the effect of different types of calcium pimelate on crystallization and melting behaviors of polypropylene (PP) were investigated.The chemical structure of calcium pimelate was confirmed by Fourier-transform infrared spectroscopy,and the crystallization and melting characteristics of PP/calcium pimelate compounds were determined by differential scanning calorimetry.The results indicated that these three types of calcium pimelate exhibited a nucleation capability for the crystallization of PP,which leads to an increase in crystallization temperature by 4.9 °C for PP/D-CaPi and PP/N-CaPi compounds and 6.5 °C for PP/ S-CaPi compound.Moreover,S-CaPi was found much easier to induce β-form crystals for PP than D-CaPi and N-CaPi,and it could result in the formation of 84.5 % β-crystals for PP.%分别采用复分解反应法(D-CaPi)、中和反应法(N-CaPi)以及硬脂酸钙与庚二酸共混法(S-CaPi)3种不同方法制备了庚二酸钙,研究了3种庚二酸钙对聚丙烯结晶和熔融行为的影响.利用傅里叶变换红外光谱仪和差示扫描量热仪测试了庚二酸钙的结构及庚二酸钙改性聚丙烯的结晶和熔融行为.结果表明,3种制备方法都可以使庚二酸完全反应得到庚二酸钙;3种庚二酸钙对聚丙烯均有成核能力,其中D-CaPi和N-CaPi使聚丙烯结晶峰温度提高了约4.9°C,S-CaPi使聚丙烯结晶峰温度提高了6.5°C,同时,S-CaPi对于聚丙烯β晶型得诱导能力明显优于D-CaPi和N-CaPi,可使改性聚丙烯中的β晶型相对含量达到84.5%.
    • 任莉平; 陈忠湖; 郑迁; 蔡艳华
    • 摘要: 采用酰化和氮化反应合成了3种不同结构的芳香族水杨酰肼衍生物,考察其对聚乳酸(PLLA)非等温结晶行为、熔融行为和热稳定性的影响.结果显示:随着芳香族水杨酰肼衍生物中酰胺基团数目的增加,其改性PLLA材料的非等温结晶峰向高温方向移动,且结晶峰也更加尖锐,表明酰胺结构有利于促进PLLA的结晶;与芳香族水杨酰肼衍生物相比,改性PLLA材料等温结晶后的熔融行为受结晶温度的影响更大;热稳定性测试显示芳香族水杨酰肼衍生物的加入会降低PLLA的起始分解温度,但不会改变PLLA的热分解趋势.
    • 丁律; 杨荣; 张鑫; 李锦春
    • 摘要: 将主链型液晶聚酯(PBDPS)大分子β成核剂与等规聚丙烯(i PP)熔融共混,得到不同添加量的i PP/PBDPS样品。利用差示扫描量热分析、X射线衍射、偏光显微镜等研究了i PP和PBDPS共混物的等温结晶动力学、结晶熔融行为、晶型结构和结晶形态。结果表明,i PP和i PP/PBDPS共混物的等温结晶动力学适用于Avrami方程,Avrami指数(n)从2. 62~2. 81变为2. 60~3. 25,晶体的生长方式为二维生长与三维生长并存。PBDPS起到异相成核作用,i PP结晶速率常数(K)随着PBDPS的添加而增大,半结晶时间(t1/2)随之缩短。使用Arrhenius方程计算了等温结晶活化能,并通过HoffmanWeeks外推法得到了i PP/PBDPS中α、β晶的平衡熔点。液晶高分子PBDPS能有效诱导i PP形成β晶型,β晶含量随着PBDPS添加量与结晶温度的提升而增大,当PBDPS质量分数为4%,结晶温度为130°C时,β晶含量高达92. 5%。
    • 姚忠亮; 曹宁宁; 郑玉婴; 邱尚长
    • 摘要: Polypropylene (PP)-based composites containing multi-wall carbon nanotubes (MWCNTs) with contents of 1.0 wt %~5.0 wt % were prepared by melting extrusion,and their thermal,crystallization,mechanical and electrical properties were investigated.The results indicated that the MWCNTs were dispersed in the matrix in two modes,i.e.existing in grain and distributing along the grain boundaries.These two modes are beneficial to the improvement of mechanical properties,heat distortion temperature and melt flow rate for the composites.As the content of MWCNTs reached 3.0 wt %,the composites exhibited an electrical percolation behavior,with which the composites exhibited excellent conductivity at room temperature.The polarizing microscopy showed that PP grains became smaller due to the addition of MWCNTs,and the grain size tended to decrease with an increase of MWCNTs content.XRD measurement demonstrated that the presence of MWCNTs did not influence the crystal form and crystalline structure of PP.In addition,MWCNTs could act as a nucleating agent to enhance the crystallinity of PP,thus resulting in a shift of α-crystallization peak to a high temperature with an increase of crystallization temperature and improving the thermal stability significantly.%通过熔融挤出法制备了多壁碳纳米管(MWCNTs)含量为1.0%~5.0%(质量分数,下同)的聚丙烯(PP)/MWCNTs复合材料,并对其热稳定性、结晶性能、力学性能和电性能等进行了研究.结果表明,复合材料中MWCNTs以2种方式存在,一是MWCNTs存在于晶粒中,二是MWCNTs沿晶界分布,2种方式协同作用,改善了复合材料的力学性能、热变形温度和熔体流动速率;当MWCNTs含量为3.0%时,复合材料表现出电渗流行为;加入MWCNTs后,PP晶粒尺寸减小,晶粒明显细化,随着MWCNTs含量增加,晶粒尺寸进一步减小,但并未改变晶体结构;MWCNTs为PP的α晶成核剂,α晶熔融峰位置随结晶温度的升高而逐渐向高温移动.
    • 张跃飞; 周培章; 杨鑫; 林祥凤
    • 摘要: 合成了1,3,5-苯三甲酰三(叔丁胺)(BTA-TB),1,3,5-苯三甲酰三(异丁胺)(BTA-IB)和1,3,5-苯三甲酰三(正丁胺)(BTA-NB)成核剂,并研究了其对聚丙烯结晶和熔融行为的影响.与高效商用环状二羧酸盐类聚丙烯成核剂HPN-68对比,结果表明,这三种成核剂均为高效的聚丙烯α晶型成核剂,最适添加量分别为0.25%,0.15%和0.25%,最适添加量下BTA-TB、BTA-IB和BTA-NB使聚丙烯结晶温度从124°C分别提升至130.4、130.1和130.2°C,与HPN-68在添加量0.25%下的成核效果相当.%1,3,5-benzenetricarboxylic acid tris (tert-butylamide) (BTA-TB),1,3,5-benzenetricarboxylic acid tris (sec-butylamide) (BTA-IB) and 1,3,5-benzenetricarboxylic acid tris (butylamide) (BTA-NB) were prepared as nucleating agents for polypropylene (PP),and the effects of the obtained nucleating agents on the crystallization and melting behaviors of PP were investigated by using differential scanning calorimetry (DSC).The properties of PP nucleated with BTA-TB,BTA-IB and BTA-NB were compared with those of PP nucleated with highly efficient commercial nucleating agent HPN-68.The results show that BTA-TB,BTA-IB and BTA-NB are highly efficient nucleating agents for α-form PP compared with HPN-68.The optimal addition amount of BTA-TB,BTA-IB and BTA-NB in PP is 0.25wt%,0.15wt% and 0.25wt%,respectively.Under the optimal addition amount,the incorporation of BTA-TB,BTA-IB and BTA-NB into PP increases the crystallization peak temperature from 124 °C of pure PP to 130.4 °C,130.1 °C and 130.2 °C,respectively,which is close to the nucleating effect of HPN-68 at addition amount of 0.25wt%.
    • 蔡艳华; 赵莉莎
    • 摘要: To rich the category of crystallization accelerator with bisamide structure of poly (L-lactic acid) (PLLA),N,N'-bis(salicyl) decanedioic acid dihydrazide (SS),as a crystallization accelerator for PLLA,was synthesized from decanedioic acid and salicyl hydrazide,and the influence of SS on the non-isothermal crystallization and melting behavior of PLLA was investigated.The non-isothermal crystallization behavior results showed that SS can significantly promote the crystallization of PLLA,in particular,0.5% SS exhibited the best crystallization accelerating effect for PLLA,and 0.5% SS caused the onset crystallization temperature,non-isothermal crystallization peak temperature,and the non-isothermal crystallization enthalpy to increase from 101.4 °C,94.5 °C,and 0.1 J/g to 122.8 °C,119.5 °C,and 32.6 J/g,respectively.In addition,the cooling rate was also very important factor to affect the crystallization behavior of PLLA.However,the effect of the set final melting temperature on the non-isothermal crystallization of PLLA/SS was negligible.The melting behavior of PLLA/SS after isothermal crystallization further confirmed the effect of different SS concentration on the crystallization of PLLA,however,this difference can decrease with an increase of isothermal crystallization time.%为丰富双酰胺类聚L--乳酸结晶促进剂的类别,以癸二酸和水杨酰肼为原料制备具有双酰胺结构的癸二酸二水杨酰肼作为聚L--乳酸的结晶促进剂,研究其对聚L--乳酸的非等温结晶行为和熔融行为的影响.非等温结晶行为显示癸二酸二水杨酰肼可显著提升聚L--酸的结晶能力,尤其是0.5%的癸二酸二水杨酰肼对聚L-乳酸具有最佳的结晶加速效应,可使聚L-乳酸的起始结晶温度、结晶峰温度以及非等温结晶焓分别从101.4°C,94.5°C,0.1 J/g增加到122.8°C,119.5 °C,32.6 J/g,另外,非等温结晶过程中降温速率是影响聚L-乳酸结晶的重要因素,而最终熔融温度对非等温结晶行为的影响较小.等温结晶后的熔融行为研究进一步证实了不同含量癸二酸二水杨酰肼对聚L-乳酸结晶促进作用的贡献大小,但促进作用上的差别会随着等温结晶时间的增加而减小.
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