熔体泵的特性及其在聚合物加工中的应用

齿轮泵用来输送聚合物熔体在挤出加工中得到广泛应用.本文简要介绍了这种泵的特点,应用它的好处及国内外发展概况.     

齿轮泵在高分子材料成型加工中的应用及特点

介绍了齿轮泵在橡胶、塑料成型加工中的应用及特点。齿轮泵与挤出机组合一起使用，这种组合不仅获得了很高的恒定物料压力，同时挤出均匀、稳定，挤出温度也很低。     

单螺杆挤出机一熔体泵串联挤出系统的性能与应用

上世纪80年代至90年代中，熔体泵挤出技术在工业发达国家取得了高速发展，它在塑料挤出加工业的应用已涉及造粒、挤板(片、膜)、挤管、吹膜、挤出涂敷、型材挤出、连续吹塑等领域，加工的材料几乎涉及所有的热塑性树脂、热塑性弹性体     

塑料加工中的综合性助剂——含氟聚合物加工助剂

由于含氟聚合物加工助剂(PPA)在基础树脂中能够形成聚合物熔体／低表面能聚合物“涂层”／金属的结构，可使被加工的聚合物畅通地滑过界面，明显降低加工时的剪切应力，从而对树脂加工性能、产品质量、能源消耗、生产效率、机械磨损都有不同程度的改善。     

茂金属聚合物的加工与应用现状

综述了茂金属聚合物加工对工艺和设备的要求,同时对茂金属聚合物的应用现状和发展趋势做了探讨。     

聚合物加工用润滑剂的应用现状与发展趋势

介绍了聚合物加工用润滑剂的应用现状、产品结构与分类,以及近年来润滑剂的作用机理研究情况及科研产业化成果;提出了发展环保清洁工艺,生产高效能、耐高温、无毒害、高附加值新型产品才是润滑剂行业未来的发展方向。     

聚合物凝胶的研究与应用

聚合物凝胶是一类具有独特物理、化学性质的聚合物网络和溶剂组成的体系 ,在众多的领域具有广泛的应用。综述了聚合物凝胶的制备、结构与性能及应用方面的研究进展     

塑料薄膜加工用塑料助剂的类别及应用

塑料助剂是为了改善树脂的加工性能和使用性能而加入的化学品。通常所用的塑料助剂有十几类，随着塑料品种的增多，用途的扩大和加工技术的不断进步，助剂的类型和品种也日益增多。     

粉末橡胶的开发与应用(一)

1概述粉末橡胶是橡胶原料形态的重大改革,对于橡胶工业提高混炼效率,降低动力消耗以及进一步推进生产连续化具有重要意义。长期以来,橡胶工业使用的原材料一直是一种块状橡胶,每块重量达25~50kg。这种块状橡胶不仅给搬运和配料带来不便,还需要切成小块称量,同时在混炼时也要消耗很大动力才能将其碾碎、混合,每千克橡胶约耗用2~3kWh的动力。现在,橡胶厂有一半以上的电能是消耗在炼胶上面。为了提高橡胶加工效率,使胶料混炼均匀,密炼机已普遍大型化到270L。大型轮胎厂更广泛采用370L和620L的密炼机,近年还出现了800L的庞大炼胶机组。因此,为…     

稀土热稳定剂的开发与应用

稀土热稳定剂具有许多优点，如优异的热稳定性能，促进熔融作用，加工性能好，独特的偶联、增容、内增塑、增韧作用，优良的透明性，独特的增艳功能，优异的耐候性能以及优异的电绝缘性能；无毒，安全卫生等。     

The application of melt elasticity to polymer processing

The present state of knowledge of polymer melt elasticity is reviewed together with consideration of the problems that elastic effects cause in polymer processing systems. Two examples of the useful application of melt elasticity are presented, one in melt extrusion the other in polymer melt mixing.     

The application of melt elasticity measurements to polymer processing

In recent years there has been increasing recognition of the importance of melt elasticity in polymer processing. A new instrument has been developed that determines the elastic properties of polymers in the melt state by measuring both the stress relaxation and strain recovery characteristics as a function of applied rate of strain, temperature, and magnitude of applied strain. Data on several different polymers will be presented together with examples of the significance of melt elasticity in such processing operations as thermoforming, blow molding, and film forming. A material parameter that is very important in the processing of polymers such as polystyrene and poly(methylmethacrylate) is the transition above the glass transition, T_g, referred to as the liquid-liquid transition, T_II. At this transition there is an abrupt change in the elasticity of the melt. Processing above or below this transition produces products with very different end use properties.     

熔体齿轮泵国产化的探讨

叙述了国内外熔体齿轮泵的现状和发展趋势,并对熔体齿轮泵的主要零件的材料和熔体齿轮泵国产化的必要性进行了详细的论述。     

熔体输送齿轮泵的失效分析

通过对熔体泵失效现象进行分析,指出了导致熔体泵失效的原因,并提出了改进措施。     

Simulation of polymer melt processing

Polymer melt processing requires an integration of fluid mechanics and heat transfer, with unique issues regarding boundary conditions, phase change, stability and sensitivity, and melt rheology. Simulation has been useful in industrial melt processing applications. This brief overview is a personal perspective on some of the issues that arise and how they have been addressed. © 2009 American Institute of Chemical Engineers AIChE J, 2009     

一种新型的塑料熔体齿轮泵转子相位调整方法

介绍一种新型塑料熔体齿轮泵转子相位的调整方法,应用本方法安装双输出轴的熔体齿轮泵转子能保证两转子之间侧隙的精确度,且操作简单。     

终缩聚熔体齿轮泵稳定运行探索

通过对聚酯装置增容和后接直纺长丝前后熔体齿轮泵工况变化的统计分析,研究其运行不稳定的原因,提出改造措施,包括滑动轴承润滑油槽,齿轮泵的机械密封,降低齿轮泵出口压力,改自动提速为手动提速等等。     

PET熔体齿轮泵转速的控制

介绍了在连续缩聚装置中熔体齿轮泵转速的2种不同控制方式:流量控制和压力控制。详细阐述了流量控制和压力控制的影响因素、优缺点,并且提出了解决办法。     

熔体输送齿轮泵故障分析及稳定运行措施

熔体齿轮泵是聚酯生产装置中的关键设备,一旦发生故障,将导致整套聚酯生产装置停车。通过对熔体齿轮泵故障分析,找出原因,通过积极维护、规范操作,延长了熔体齿轮泵稳定运行周期,节约大量检修费用。     

Performance of gear pumps in polymer processing

Within the past several years considerable interest has developed in the practice of retrofitting plasticating extruders with gear pumps. The primary motivation for this is to reduce surges and fluctuations in the extrusion rate, thereby improving product quality and reducing waste. It is shown that the effectiveness of a gear pump for this purpose is directly related to its volumetric efficiency, which depends upon the pump dimensions, the flow behavior of the polymer, and the operating variables of temperature, pressure differential, and pump speed. Experimental data on three thermoplastic materials using a pump having gear wheels of 36 mm diameter for both leakage and power are reported. These data have been correlated with semi-empirical equations.