尼龙-1010非等温结晶动力学

<正> 尼龙-1010是我国独创的工程塑料品种,已被较广泛地应用于精密机械零件、仪表制造、家用电器、航空等方面。有关尼龙-1010的基础研究大多在我国学者中间进行,由于在实际加工生产过程中,如通常的融熔纺丝、注射、模压等工艺均是在非等温条件下进行,有关它的非等温结晶动力学尚未见报道,本文用几种理论方法对尼龙-1010的非等温结晶动力学过程进行研究。     

尼龙1010非等温结晶动力学与机理研究

尼龙１０１０非等温结晶动力学与机理研究朱诚身，王经武，李卓美（郑州大学材料工程系郑州４５００５２）（中山大学高分子研究所广州５１０２７５）关键词尼龙１０１０，非等温结晶动力学，结晶机理，动力学结晶能力尼龙１０１０的结晶动力学，无论是等温还是非等温，研...     

尼龙1010非等温结晶动力学过程的计算机模拟

根据Ъорохоъский提出的相似于Avrami方程的近似公式 X =1 -exp[-Z(at) n],采用加权最小二乘法 ,对尼龙 1 0 1 0非等温结晶动力学过程进行了模拟 ,编制了模拟非等温结晶动力学过程的软件。该软件可用于精确处理结晶动力学参数 ,也可用于计算机辅助教学。     

测定高聚物动力学结晶能力的非等温DSC方法

研究了从非等温ＤＳＣ结晶曲线计算高聚物动力学结晶能力的方法．从高聚物非等温结晶动力学微分方程出发导出了计算高聚物动力学结晶能力的新方程．以含有不同催化剂的聚对苯二甲酸乙二酯为例，对其结晶进行了测试与计算．发现合理地选定最快结晶速率温度是计算动力学结晶能力的关键．本方法所得动力学结晶能力能正确反映高聚物的整体结晶信息     

高聚物非等温结晶动力学

由于等温ＤＳＣ法测定结晶动力学参数在实验上存在着一定的局限性，这些缺点可通过非等温ＤＳＣ法来克服。本文基于上述观点介绍了高聚物非等温结晶动力学的理论和实验方法，并对影响动力学过程的一些因素进行了讨论，对非等温结晶动力学的最新情况及发展倾向，应用情况作了介绍。     

尼龙1O1O非等温结晶动力学过程的计算机模拟

根据ъорοхоъский提出的相似于Avrami方程的近似公式X=1-exp[-Z(at)n],采用加权最小二乘法,对尼龙1010非等温结晶动力学过程进行了模拟,编制了模拟非等温结晶动力学过程的软件.该软件可用于精确处理结晶动力学参数,也可用于计算机辅助教学.     

烷基取代聚噻吩的非等温结晶动力学

根据ＤＳＣ测得的数值,采用Ｊｅｚｉｏｒｎｙ ,Вороховский和由作者实验室提出的一种新方法研究了十二烷基取代聚噻吩（Ｐ３ＤＤＴ） 和十八烷基取代聚噻吩（Ｐ３ＯＤＴ） 的非等温结晶过程,并应用Ｋｉｓｓｉｎｇｅｒ 法求取其结晶表观活化能ΔＥ,探讨了不同烷基取代基团对结晶过程的影响．Ｐ３ＤＤＴ 应用Ｊｅｚｉｏｒｎｙ 和Вороховский法描述时在结晶后期均发生偏离现象,而作者提出的新方法描述时则得到较好的线性关系．求得Ｐ３ＤＤＴ 的ΔＥ 为１８４－７９ｋＪ／ｍｏｌ,Ｐ３ＯＤＴ 的ΔＥ 为２４６－９３ｋＪ／ｍｏｌ,比较结晶表观活化能数值可知,Ｐ３ＤＤＴ 比Ｐ３ＯＤＴ 更易结晶．     

半芳香尼龙6T/66的合成和非等温结晶动力学的研究

采用成盐、预聚合、固相聚合三步法制备高分子量的PA6T/66,用差示扫描量热法(DSC)研究了PA6T/66的非等温结晶动力学,结果表明:结晶温度随着降温速率的增大而降低;半结晶期T1/2随降温速率Ф的增大呈指数下降,表明结晶速率随降温速率的增大而提高;由用R-T法可以得到在不同结晶度下lgΦ对lgT有较好的线性关系。用Kissinger方法计算得到PA6T/66(55/45)非等温结晶活化能分别为ΔE=-61.51kJ/mol。     

尼龙6/蒙脱土纳米复合材料非等温结晶动力学和透明性研究

将有机化的蒙脱土与尼龙6(PA6)在Haake共混机中共混,制备出尼龙6/蒙脱土纳米复合材料(PA6N);对尼龙6/蒙脱土纳米复合材料和纯尼龙6分别进行差示扫描量热法非等温结晶试验,以了解蒙脱土在尼龙6/蒙脱土纳米复合材料中的成核作用、扩大尼龙6在包装领域的应用范围.与此同时,采用偏光显微镜测定了样品的结晶形态;采用紫...     

尼龙6/蒙脱土纳米复合材料的等温结晶动力学研究

用ＤＳＣ法研究了熔体插层制备的尼龙６／蒙脱土纳米复合材料的等温结晶行为．结果表明,加入少量的蒙脱土可明显提高尼龙６的结晶速率,降低球晶径向生长的单位面积表面自由能．从Ａｖｒａｍｉ方程和Ｈｏｆｍａｎ理论出发,得出蒙脱土纳米粒子的存在可明显改变尼龙６的结晶行为     

MELTING CRYSTALLIZATION BEHAVIOR OF NYLON 66

Analysis of isothermal and nonisothermal crystallization kinetics of nylon 66 was carried out using differentialscanning calorimetry (DSC). The commonly used Avrami equation and that modified by Jeziorny were used, respectively, tofit the primary stage of isothermal and nonisothermal crystallizations of nylon 66, In the isothermal crystallization process,mechanisms of spherulitic nucleation and growth were discussed. The lateral and folding surface free energies determinedfrom the Lauritzen-Hoffman treatment are σ= 9.77 erg/cm~2 and σ_e= 155.48 erg/cm~2, respectively; and the work of chainfolding is q = 33.14 kJ/mol. The nonisothermal crystallization kinetics of nylon 66 was analyzed by using the Mo methodcombined with the Avrami and Ozawa equations. The average Avrami exponent n was determined to be 3.45, Theactivation energies (ΔE) were determined to be -485.45 kJ/mol and -331.27 kJ/mol, respectively, for the isothermal andnonisothermal crystallization processes by the Arrhenius and the Kissinger methods.     

高岭土填充尼龙6的结晶行为

利用差示扫描量热仪（ＤＳＣ）研究了未处理高岭土和经γ－缩水甘油醚氧丙基三甲氧基硅烷（ＫＨ５６０）处理的高岭土对尼龙６等温和非等温结晶行为的影响．结果表明，未处理的高岭土和ＫＨ５６０处理的高岭土在尼龙６基体中都起到异相成核作用．但是，与未处理高岭上相比，ＫＨ５６０处理的高岭土更有效地提高了尼龙６的结晶速率．这一方面归因于ＫＨ５６０处理的高岭土在尼龙６中的分散性好，增大了成核密度；另一方面归因于高岭土经ＫＨ５６０处理后，与尼龙６的相容性增强，从而提高了尼龙６的晶体生长速率．     

A STUDY ON THE CRYSTALLIZATION KINETICS OF NYLON 1010

The kinetic behavior of isohermal and nonisothermal crystallization of nylon-1010has been studied by means of dilatometry and differential scanning calorimetry, respec-tively. The isothermal and nonisothermal process can be descibed by Avrami equationand Ozawa equation, respectively. From the experimental results the kinetic paramters ofcrystallization and crystalline mechanism for isothermal and nonisothermal measurementsare discussed.     

ON A DIFFERENTIAL EQUATION FOR KINETICS OF NON- ISOTHERMAL CRYSTALLIZATION

A new differential equation was derived from the modified first-order kinetic model to describe the polymer crystallization processes. The crystallization experiments were carried out by means of DSC. Poly (ethylene terephthalate) resins were selected as the samples containing different catalysts. The relationships between the parameters obtained from the known Avrami equation and from one in the present paper were discussed. A method for applying the equation to determine the kinetic parameters from a constant heating and a constant cooling curve was proposed.     

CRYSTALLIZATION AND MELTING OF NYLON 610

Differential scanning calorimetry was used to study the crystallization andmelting of nylon 610. For nylon 610 crystallized from the melt state (260℃), the overall rateof bulk crystallization can be described by a simple Avrami equation with Avrami exponentn ≈ 2, independent of crystallization temperature. With the experimentally obtainedT_m~0 (235℃ ～ 255℃) of nylon 610, the fold surface free energy σ_e was determined to be35 ～38 erg/cm~2. The effects of annealing temperature and time on the melting of quenchednylon 610 were also investigated. For nylon 610 quenched at room temperature there isonly one DSC endotherm peak DSC scans on annealed samples exhibited an endothermpeak at approximately 10℃ above the annealing temperature. The size and position of theendothermic peak is strongly related to annealing temperature and time. An additionalthird melting was observed when quenched nylon 610 was annealed at high temperaturefor a sufficiently long residence time. The existence of the third melting peak suggests thatmore than one kind of distribution of lamella thickness may occur when quenched nylon610 is annealed. The implications of these results in terms of crystal thickening mechanismwere discussed.     

尼龙6/蒙脱土纳米复合材料的结晶行为

用广角Ｘ 射线衍射（ＷＡＸＤ）、差示扫描量热仪（ＤＳＣ）、小角激光散射（ＳＡＬＳ）等手段研究了尼龙６／蒙脱土纳米复合材料的结晶行为．结果表明分散在尼龙６基体中的蒙脱土纳米粒子起成核剂的作用．蒙脱土的表面改性增加了蒙脱土和尼龙６分子之间的界面粘接，它具有阻碍尼龙６结晶的作用，使结晶活化能增加     

阻燃聚丙烯体系结晶动力学研究

本工作利用JJY-1型结晶速率仪对几种典型的阻燃聚丙烯共混体系的结晶行为进行了研究,发现不同的阻燃剂对PP的结晶行为有不同的影响。阻燃剂APP对PP的结晶具有较强的成核作用。但过量的APP对PP结晶生长有明显的阻碍作用。阻燃剂TBE对PP结晶也体现异相成核作用。阻燃剂PER由于增加PP结晶过程的分子链段折叠能而对PP结晶起阻碍作用。阻燃剂TPP对PP的结晶行为影响较弱。     

不同分子量尼龙1010的结晶与熔融

不同分子量尼龙１０１０的结晶与熔融＊朱诚身王经武王友文杨桂萍（郑州大学材料工程系郑州４５００５２）陈玉莫志深（东北师范大学分析测试中心长春１３００２４）（中国科学院长春应用化学研究所长春１３００２２）关键词尼龙１０１０，分子量，结晶，熔融＊１９９４＿...