Effect of Electron Irradiation on Polypropylene Films

Effects of both electron beam irradiation on the properties of polypropylene （PP） films and the irradiation on the different layers of a multilayer PP film are studied. A Fourier transform infrared spectroscope was used to investigate the chemical structure of the films. The results showed that the chemical properties of the first layer were improved, that is, more functional groups responsible for dye ability and hydrophilicity of the film were produced on its surface, while noticeable improvement was not detected on the surface of other layers. This was also confirmed by testing the dye ability of the layers. However, the results obtained by atomic force microscopy showed that the electron irradiation caused some topographical changes, not only on the surface of the first layer but also on the others.

THE STUDY ON CHLORINATED POLYPROPYLENE (PPCI)-POLYPYRROLE (PPy) COMPOSITE FILM

The chlorinated polypropylene-polypyrrole composite film was synthesized by means of a newmethod for the first time. The effects of various conditions on polymerization and the electric con-ductivity of PPCl-PPy composite film were investigated. It was found that PPCl-FeCl3 mixturehad an excellent film-forming ability and PPCl-PPy composite film could attain high conductivityat low content of polypyrrole and was stable for heat and atmosphere.

Plasma Surface Functionalization of Biaxially Oriented Polypropylene Films with Trimethyl Borate

The radiofrequency plasma (13.56 MHz) was employed to polymerize trimethyl borate (TMB) monomer/N2 gas mixture on the surface of biaxially oriented polypropylene (BOPP) films. Plasma polymer coated polypropylene films were examined by flame retardancy test (limiting oxygen index, LOI). The highest LOI value calculated for the untreated BOPP sample was 18.4 (v/v O2%) and 24.2 (v/v O2%) for the 55 W 30 minutes treated sample. The plasma polymers were characterized by FTIR spectroscopy and AFM. According to the FTIR results, the -OH, B-CH3, B-O, and BH2 functional groups were detected. It was found that the highest surface roughness belonged to 40 W 30 min treated BOPP sample which was calculated as 9.78 nm (10 μm × 10 μm). Moreover, the wettability of the modified BOPP film surfaces was characterized via contact angle measurements. The water contact angle values have decreased from 109.6? to the lowest value of 68.2? after the plasma treatment. The results showed that TMB/N2 plasma modification could be used as an alternative method for the enhancement of flame retardancy and hydrophilicity of BOPP film.

Properties of PEG/thermally modified wood flour/polypropylene (PP) composites

In order to improve the dimensional stability of wood-polymer composites, wood flour pre-treated by polyethylene glycol （PEG） at two different concentrations and then thermally treated at 140℃, was used as raw material to produce wood flour/poly- propylene （PP） composites at a wood content of 40%. The structure of modified wood flour was analyzed with a scanning electron microscope （SEM） and its effect on the physical and mechanical properties of wood flour/PP composites was evaluated. The SEM results indicated the ＂bulking＂ effect of PEG on wood flour, which resulted in reduced water uptake. The combination of PEG and heat treatment further improved the moisture resistance of the composites. However, PEG modification had a negative effect on the flexural modulus of rupture （MOR） and the modulus of elasticity （MOE）; whereas heat treatment partly compensated for this reduc- tion. For dynamic mechanical properties, PEG treatment decreased the storage modulus （E＇）. However, the heat treatment resulted in an increase orE＇ of the wood flour/PP composites, with the temperature of loss factor peaks shifting to a higher temperature.

Coupling effect of pond ash and polypropylene fiber on strength and durability of expansive soil subgrades:An integrated experimental and machine learning approach

This study explores the coupling effect of pond ash(PA)and polypropylene(PP)fiber to control the strength and durability of expansive soil.The PA is used to chemically treat the expansive soil and PP fiber is adopted as reinforcement against tensile cracking.The sustainable use of PA and PP fiber are demonstrated by performing mechanical(i.e.unconfined compressive strength,split tensile strength and ultrasonic pulse velocity),chemical(pH value,electrical conductivity and calcite content),and microstructural analyses before and after 2nd,4th,6th,8th and 10th freezing-thawing(F-T)cycles.Three curing methods with 7 d,14 d and 28 d curing periods are considered to reinforce the 5%,10%,15%and 20%PA-stabilized expansive soil with 0.25%,0.5%and 1%PP fiber.In order to develop predictive models for mechanical and durability parameters,the experimental data are processed utilizing artificial neural network(ANN),in association with the leave-one-out cross-validation(LOOCV)as a resampling method and three different activation functions.The mechanical and durability properties of the PA-stabilized expansive soil subgrades are increased with PP fiber reinforcement.The results of ANN modeling predict the mechanical properties perfectly,and the correlation coefficient(R)approaches up to 0.96.

Alternative Diesel Grade Fuel Transformed from Polypropylene (PP) Municipal Waste Plastic Using Thermal Cracking with Fractional Column Distillation

Day by day worldwide use of plastics is increasing because of their light weight and durable characteristics. Waste plastics are major environmental problems all over the world. Waste plastics are not bio-degradable, it remains in the landfill for a long period of time causing vegetation and aquatic ecosystem dilemmas. Abandoned waste plastic thrown into the ocean causes friction of ocean waves and then broken down by sunlight into small pieces and takes the shape of plastic like soup. Aquatic organism mistakes the plastic soup as their food and can’t digest, either they die or through food chain it affects human health. To avoid severe environmental degradation problems of waste plastics some countries and big cities banned or restricted the use of plastic products. The worldwide generation of waste plastics is approximately 280 million tons/year. All most all of these waste plastics are dumped either in land or ocean. City municipalities spend huge amount of money each year just to dispose of these waste plastics into landfill because most waste plastics are not recycled. When the waste plastics are subjected to incineration, they release harmful toxic gas into the environment causing severe pollution. These waste plastics gradually enhance the hazardous environmental problems. Generally plastics are made from crude oil, however crude oil is a very limited natural resource and non-renewable. Every year millions of barrels of crude oil are to produce the waste plastics and when plastics are discarded after use the energy source is lost. A new developed technology plan minimizes the environment pollution problems simultaneously boost up energy sector by renovating the waste plastics into high energy content fuel. The produced fuel is obtained using a unique thermal degradation of waste plastics and converting them into hydrocarbon fuel like materials. Preliminary tests proved that this fuel burns cleaner and the production cost is very low. Unique production setup demonstrated to produce 93% fuel from waste plastic in the pilot scale. The Fuel produced has been tested and proven to work on majority types of internal combustion engines. This technology utilized can avoid waste plastic pollution problem worldwide by the implementation of newly developed technology. Through the utilization of the technology the use of reliable plastics won’t need to be banned and serve as a very reliable alternate source of energy. The technology will also help reduce a significant amount of import oil from foreign countries and help provide a steady economy.

电容器用BOPP薄膜在介电和储能性能提高中的研究进展

目前商用薄膜电容器以双向拉伸聚丙烯材料(BOPP)为主,其作为薄膜电容器的关键材料是最常用的聚合物薄膜,但BOPP薄膜作为电容器的核心材料仍存在储能密度低和使用温度偏低等问题。本文综述了近几年研究学者对电容器用BOPP薄膜在电介质材料的介电及储能性能提升方面的研究,为高性能聚合物基电介质材料的研究和发展提供了参考,并对未来的研究方向进行了展望。

低摩擦因数热收缩BOPP包装薄膜的开发

研究了一种高性能BOPP薄膜的开发,采用特殊的原料配方和加工工艺制备。通过与标准型BOPP薄膜对比,跟踪30天内第1天、第7天、第15天、第30天的摩擦因数、热收缩率、光学性能,分析数据得出新开发薄膜的各性能都有所优化。该BOPP薄膜具有低摩擦因数、高热收缩性能和良好的光学性能。

Mechanical, Thermal and Crystallization Properties of Polypropylene (PP) Reinforced Composites with High Density Polyethylene (HDPE) as Matrix

Our work aims to evaluate a complete outlook of virgin high density polyethylene (HDPE) and polypropylene (PP) polyblends. Virgin PP of 20, 30 and 50 weight% is compounded with virgin HDPE. The properties like tensile strength, flexural strength, Izod impact strength are examined. Scanning electron microscopy (SEM) and polarised light microscopy (PLM) are used to observe the surface and crystal morphology. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) tests verify the non compatibility of both polymers. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) techniques are used to study the thermal behaviour of composites. The results manifest co-occurring spherulites for polyblends;indicating the composite to be a physical blend of continuous and dispersed phases, but on the other hand PP improves the tensile and flexural properties of HDPE.

镭射BOPP基膜循环拉伸力学性能的试验研究

目的为研究双向拉伸聚丙烯(Biaxially Oriented Polypropylene,BOPP)薄膜在重复拉伸使用后的弹性模量变化以及应变变化趋势。方法以26μm BOPP薄膜为研究对象,以1、1.5、2、2.5、3、3.5、4 N为最大加载力分别进行加载周期为15次的单轴循环拉伸试验,总结对比循环次数以及加载力对弹性模量及棘轮应变的影响,分析薄膜性能变化趋势。结果通过对比同一加载应力不同循环下的弹性模量以及棘轮应变,发现在预设加载力下随着循环次数增加,薄膜弹性模量呈增大趋势,且增大幅度逐渐减小,其棘轮应变与弹性模量变化趋势一致;通过取均值对比不同加载力下的弹性模量以及棘轮应变变化,发现薄膜弹性模量随加载力增大而先增大后减小,最大应变以及最小应变均随加载力的增加而增大。结论通过试验研究得出了BOPP薄膜在循环拉伸中弹性模量及棘轮应变随加载力、循环次数增大的变化趋势;对薄膜性能变化有了一定的预测,并为实际加工中的张力选择提供了指导性建议。

MECHANICAL PROPERTIES OF CHLORINATED POLYPROPYLENE——POLYPYRROLE FILM

The chlorinated polypropylene (PPC1)-polypyrrole (PPy) conducting films were successfully synthesized by a novel method for the first time. The mechanical properties of PPC1-PPy conducting films were investigated by means of stress-strain test and DMA. It was shown that the rupture strength and initial modulus increase with the increase of polypyrrole content , but the elongation at rupture decrease. Besides, the glass transition temperature (Tg) is increasing to a plateau when polypyrrole content attains 6%. Moreover, a new mechanical model to describe the mechanical properties of PPC1-PPy blend system is established by changing the correction factor in Mooney model. It was found that the theoretic value of the model is well coincident with the experimental results.

Research and development of 3PP coating steel pipes

The industrial application of an exterior three-layer anticorrosive polypropylene coating system(3PP)on large-diameter(larger than Φ600 mm)steel pipes was developed using an experimental process simulation study and the optimization of raw materials inspection,steel pipe surface pretreatments,and water cooling control on a coating application process.The coating properties meet ISO standard 21809 on buried or submerged 3PP pipelines used in the petroleum and natural gas industries.Differential scanning calorimetry and X-ray diffraction were used to analyze the crystallinities and grain sizes of polypropylene(PP)top coats with different cooling rates.Increasing the melt cooling rate reduces the crystallinity and grain size of the PP top coat and enhances its strength and toughness.

丙烯等规配位聚合催化剂及电容器膜基材iPP的制备技术研究进展

生产包括电容器膜基材iPP在内高端聚丙烯的关键技术是丙烯高等规聚合的高活性催化剂和先进聚合工艺。本文详细介绍了丙烯聚合催化剂的发展历程,包括高效Ziegler-Natta催化剂、茂金属催化剂和非茂金属催化剂,指出了在合成电容器基材iPP方面此三类催化剂的优缺点。阐述了烯烃聚合催化剂的近期发展动态:产生了在催化剂结构/组成中引入强吸电子基团有利于提高催化剂活性和聚烯烃分子量的新理论,发展了新一代烯烃聚合催化剂包括内外给电子体于同一分子的丙烯聚合催化剂和全杂环金属有机催化剂,提出了制备嵌端共聚烯烃的可逆“络合-断开”配位聚合新方法。基于丙烯聚合先进工艺,结合高端电容器膜基材iPP技术指标的严苛要求,分析了聚丙烯粉料和粒料中灰分产生的主要因素,建立了在聚丙烯粉料灭活之前进入复合有机溶剂洗涤工序的生产方法,制备合格的高端电容器膜基材i PP。

BOPP光学膜专用树脂的开发与生产

为开发生产高速挤出双向拉伸聚丙烯(BOPP)光学膜专用树脂,本文通过分析BOPP专用树脂的性能要求,在双环管液相本体工艺装置上采用非对称加氢和非对称外给电子体技术生产BOPP薄膜专用树脂,同时通过对添加剂及产品性能的研究,采用高效抗氧剂B代替常规抗氧剂B215,使产品颜色性能得到显著改善,成功开发出光学膜专用树脂PPH-FA03。

模拟地震作用下PP-ECC桥墩抗弯性能试验研究

为研究聚丙烯纤维水泥基复合材料(PP-ECC)桥墩与普通混凝土桥墩在压弯荷载作用下承载力差异,本文通过拟静力试验对6个局部采用PP-ECC桥墩和2个普通混凝土桥墩的抗弯性能进行试验研究。结合PP-ECC桥墩的破坏过程,确定PP-ECC桥墩的压弯破坏的特征点,之后基于PP-ECC材料的简化本构模型推导出PP-ECC桥墩的理论开裂、屈服和极限荷载公式。对PP-ECC材料进行单轴拉伸和单轴压缩试验,得到简化PP-ECC本构模型的特征参数,通过试验结果对计算结果进行验证,并对比不同轴压比和PP-ECC区高度下桥墩的抗弯承载力、最大变形的差异。结果表明:PP-ECC桥墩在开裂之后,受拉区PP-ECC并未退出工作,而是协同受拉钢筋参与截面受力;PP-ECC桥墩在达到极限荷载时,裂缝稳态发展,没有出现普通混凝土桥墩保护层混凝土大面积剥落的情况;局部采用PP-ECC桥墩极限荷载时最大变形较普通混凝土桥墩有较大提升,且增加轴压比会降低桥墩的变形能力;在较高轴压比下增加PP-ECC区高度,桥墩的抗弯承载力提升了8.8%;使用简化本构模型计算PP-ECC桥墩特征点抗弯承载力时计算精度为0.86~1.13,且方差分析值偏小,具备良好的计算精度。

基于国产粒子的BOPP膜性能测试及高压电容器试验研究

聚丙烯薄膜是电力电容器核心材料之一,其原材料聚丙烯粒子全部依赖国外进口,为解决这一“卡脖子”问题,近年来多家高校、企业都针对电容器产业链国产化开展了许多研究。本文测试了不同聚丙烯粒子制备的聚丙烯粗化薄膜电气强度、相容性、老化性能等,测试结果表明,国产粒子制备的聚丙烯薄膜与进口粒子制备的聚丙烯薄膜性能相当,在直流电场作用下国产粒子薄膜的击穿场强高于进口粒子薄膜,但分散性较大。基于国产粒子薄膜研制的电容器通过第三方检测机构的试验认证,主要技术指标方面与进口材料电容器性能相当,表明国产粒子制备的聚丙烯粗化薄膜能满足电容器使用需求,有望替代进口粒子实现国产化。

耐刮擦高挺度BOPP专用料L5D98N开发及运用

某石化公司20×10^(4)t/a的Unipol气相工艺聚丙烯生产装置上,通过工艺参数调整和催化剂配方优选,开发耐刮擦高挺度BOPP专用料L5D98N。结果表明,主催化剂CS-1-G搭配外给电子体UD55,选用复配抗氧剂XT500和除酸剂DHT4A,在一定的工艺条件下,生产出符合下游加工使用的耐刮擦高挺度BOPP专用料。

基于改性PP-R材料研制的500 kV聚丙烯绝缘电力电缆

基于对改性PP-R聚丙烯材料的研究,根据电缆运行环境,通过采用以聚丙烯树脂和增韧弹性体为主的超净PP绝缘材料、超光滑半导PP屏蔽料,设计研发了可应用在290/500 kV电力系统中的聚丙烯绝缘电力电缆。该电缆通过平滑铝金属套设计和双焊枪焊接技术,成功解决了传统皱纹铝护套由波谷点接触所引起的质量安全风险。相比相同运行环境中的传统交联聚乙烯绝缘皱纹铝护套电力电缆,其长期工作温度可提升到105℃;电缆正常运行时的载流量在直埋土壤中可提升18.6%,在空气中可提升20.3%。

电容器用BOPP薄膜及其专用树脂研究进展

双向拉伸聚丙烯(BOPP)薄膜是电容器的重要组成部分。本文归纳了作为BOPP薄膜的聚丙烯树脂原料关键参数(灰分含量、等规度、相对分子质量、熔体流动速率、等规序列长度)及其影响规律,同时总结了BOPP电容器薄膜的现有生产工艺,并进一步对BOPP薄膜性能的提升方法进行了综述。最后,提出未来电容器用BOPP薄膜的发展重点将是超低灰分树脂原料与耐热薄膜产品。