熔体强度

但由于PP的高结晶性，熔体强度低，其发泡成型较为困难。

Nevertheless foaming processing of PP is very difficult because of its high crystallinity and poor melt strength .

线性结构的常规PET因为熔体强度差，不适用于挤出发泡成型。

Conventional PET with linear molecular structure is not suitable for extrusion foaming process due to its poor melt strength .

通过长链支化来改性PP，从而得到高熔体强度的PP。

High-melt-strength polypropylene is achieved with modified PP through long chain branching .

但PP的熔体强度低、发泡性能差，很难制得泡孔结构较好的泡沫产品。

However , the foaming property of PP is ( very ) poor because of its low melt strength .

高熔体强度棚膜专用LLDPE树脂的研制

Preparation of high melt strength LLDPE for greenhouse film

聚对苯二甲酸乙二醇酯（PET）的扩链反应是一种提高PET分子量和熔体强度的有效方法。

Chain Extension is one of an effective methods for increasing the molecular weight and improving the melt strength of Poly ( ethylene terephthalate )( PET ) .

研究表明：具有显著应变硬化行为和高熔体强度的长链支化聚丙烯是获得优质PP发泡材料的前提；

The research results showed that the long-chain branched polypropylene with remarkable strain hardening behavior and high melt strength was the premise in the production of excellent polypropylene foam .

6380M流动性好，其临界剪切速率高，但熔体强度不及单峰HDPE。

In addition , 6380 M has a good flowability and high critical shear rate , though its melt strength is inferior to unimodal HDPE .

高熔体强度聚丙烯（HMSPP）是聚丙烯的一种重要改性产品，具有广泛的用途。

High melt strength polypropylene ( HMSPP ) is an important product of polypropylene modification with wide application .

课题研究的关键是长支链接枝PP的生成以提高熔体强度以及降解、交联副反应的控制。

The hinges of this study included the formation of longer side chains in order to acquire higher bath strength and the control of degradation of iPP and cross-linking side reactions .

为了改善聚丙烯（PP）的微孔发泡性能，本文首先将PP与高密度聚乙烯（HDPE）共混，提高其熔体强度；

In order to improve the microcellular foam ability of polypropylene ( PP ), PP was firstly blended with high density polyethylene ( HDPE ) to enhance the melt strength .

实验表明：ACR加工助剂能够促进PVC体系的塑化，提高熔体强度及均匀性，对PVC的力学性能没有明显的不良影响。

The experiments showed that ACR processing additive could promote the plasticization of PVC , increase the intensity and homogeneity of melt , and had no obvious bad effects .

通过辐照法制备了长支链型高熔体强度聚丙烯（LCB-HMSPP），采用高级流变扩展系统（ARES）表征了其熔体黏弹性，采用毛细管流变仪研究了其在高剪切速率下的流变行为。

High-melt-strength polypropylene with long chain branching ( LCB-HMSPP ) was prepared via irradiation .

因此，为了提升CPP在泡沫塑料应用中的竞争力，必须对其进行改性，提高其熔体强度。

Therefore , it is need to modify the CPP properties , improve the melt strength , in order to exalt its competence in the application of foam plastics .

研究了高熔体强度聚丙烯（HMSPP）/共聚聚丙烯（PP）/低密度聚乙烯共混体系的发泡性能。

This paper studied foaming capacity of a blending system consisting of high-melt strength polypropylene ( HMSPP ), copolymer of propylene ( PP ) and low density polyethylene .

PPC的加入对PLA的结晶度无明显变化，但共混物熔体强度明显降低，导致泡孔尺寸增大。

It was found that the crystallinity of the blend did not change obviously with the adding of PPC , but the melt strength was weakened so that increased the cell size .

结果表明，PETG的熔体强度可以进行调节。

From experiment results , it can be found that the PETG melt intensity can be controlled .

通过反应挤出法对聚丙烯（PP）进行硅烷接枝交联改性获得高熔体强度PP（HMSPP），并对HMSPP的发泡性能及影响因素进行了研究。

High-melt-strength polypropylene ( HMSPP ) was prepared by silane-grafting and cross-linking of polypropylene ( PP ) through reactive extrusion , and the HMSPP foam was fabricated by extrusion .

然而PLA在加工使用中，普遍存在着质硬且脆、热变形温度低和熔体强度低等弊端，严重制约了PLA的应用，因此需进行必要的改性。

However , there are many problems such as hard and brittle texture , low heat distortion temperature and low melt strength during the processing and utilization , which have seriously hampered the application of PLA .

当熔体强度适宜时，ADC发泡剂添加量越多，在熔体中形成的气泡也越多，制品的密度越小。

And when the melt strength is appropriate , with the increase of adding ( amount ) of foaming agent ADC , the number of gas bubbles in the melts increases and the product density becomes lower .

本文采用流变学方法从剪切流变和拉伸流变两方面，通过对剪切粘度、储能模量和损耗模量、松弛时间谱和拉伸粘度的表征，对四种具有不同分子结构PET的熔体强度进行分析。

In this work , the melt strength and viscoelasticity of four types of PET was analyzed through characterization of shear rheology and extensional rheology of PETs , including the dynamic complex viscosity , storage and loss modulus , relaxation spectrum , and extensional viscosity .

熔体强度在1.0MPa以上；

The melt strength is more than 1.0MPa ;

HDPE的熔体强度很低导致发泡效果很差，而交联HDPE和回料PE都有较高的熔体强度，从而改善了制品的发泡性能，提高了制品的发泡率。

The HDPE exhibited low melt strength and led to poor foaming effectiveness . The crosslinking HDPE and recycled PE had higher melt strength , thus improving the performance of the foam products and increasing the foam rate of the products . 5 .

通过熔体强度、熔体黏度测试和熔体流动速率（MFR）、凝胶含量的变化研究了试剂体系对接枝交联改性的作用。

The effects of the agent system on the modification were investigated by testing melt-strength , melt viscosity , the changes of melt flow rate ( MFR ) and gel content .

用Jeziorny法求出的参数Zc和n随冷却速率的增加而增加，但高熔体强度聚丙烯的Zc和n值略大于线性聚丙烯的Zc和n。

The values of Z_c and n increased with increase in cooling rate , and the values of Z_c and n of high melt strength PP were higher than those of conventional PP at the same cooling rate .

寻找简单易行，成本低廉，行之有效的高熔体强度聚丙烯（HMSPP）的制备方法是制备聚丙烯发泡材料的最关键的技术。

It is the most pivotal technology to research for a simple , low costing and effective method of preparing high-melt-strength PP ( HMSPP ) .

结果显示，改性PP的MFR可降低至0.5g/10min以下，熔体强度提高4.1倍，熔体剪切黏度提高1.707倍；

The results showed that MFR of modified PP decreased to below 0.5g / 10min , and its melt-strength was improved 4.1 times , while its melt viscosity was improved 1.707 times .

而采用接枝高熔体强度聚丙烯（HMSPP）可以获得更多更好的闭孔泡孔结构。

In contrast , the more and better closed cells can be obtained in the foam structure of the high melt strength polypropylene ( HMSPP ) .

但是普通PP熔融以后，黏度急剧下降，熔体强度非常低，容易引起气泡的合并、气体的逃逸甚至泡孔的塌陷，很难得到泡孔结构好的泡沫塑料。

However , the melt viscosity and melting strength of general PP were sharply decline after melting , which lead to bubble combination , gas escape and cell collapse , so that the foamability of PP is poor and difficult to be processed to foam products with good cellular structure .

对齐鲁PE100级燃气管专用料DGDB2480HBK的力学性能、耐慢速裂纹增长性能、熔体强度等进行了研究与分析。

Studies and analyzes mechanical property , creep crack propagation resistance and melt strength of Qilu PE100 gas pipe speciality resin DGDB2480HBK .