聚丙烯英语论文范文

White pollution informationOne, what is the white pollutionThe so-called" white pollution", is one of the plastic waste pollution of the environment of an image title. It refers to the use of polystyrene, polypropylene, PVC and other polymers made from various types of life plastic products become a solid waste disposal after use, due to free throw litter, dealing with difficult degradation, resulting in the serious pollution of the environment of city.In two, the harm of white pollutionWhite pollution exist two kinds of hazards: visual pollution and potential harm.Visual pollution refers to plastic bags, boxes, cups, bowls and other scattered in the environment, give it an adverse visual stimulation, effects of environmental aesthetics.White pollution potential hazards are manifold.1, disposable plastic foam lunch boxes and plastic bags of food containing serious impact to our health. When the temperature reached 65℃, foam plastic disposable tableware of hazardous materials into food, on the human liver, kidney and central nervous system damage.We are now used for food of the ultra-thin plastic bags are generally polyvinyl chloride plastics. In the early forty years ago, people found a polyvinyl chloride plastic residual vinyl chloride monomer. When people are exposed to vinyl chloride, wrist, fingers will appear edema, sclerosis of the skin and other symptoms, may also appear splenomegaly, liver injury. In our country, we use of ultra-thin plastic bags are almost from waste plastics recycling, is composed of small enterprises or family workshops production. These plant materials used are discarded plastic barrels, basin, such as disposable syringe. During the production, first with the raw material crushing machinery into plastic particles, then plastic particles placed in a pool ( called washing disinfection ), taken out to dry, and then mechanical pressing it into film, made of a variety of plastic bags. At every meal, there is a lot of people use plastic bags of food, they don't know this behavior is not only harmful to environment, but also do harm to their body.In 2, the soil deterioration, seriously affects the growth of crops. China's current use of plastics degradation time, usually takes at least 200years. Farm waste plastic, plastic bags and long term residual in Tanaka, will affect the crop on soil moisture, nutrient uptake, inhibit the growth of crops, resulting in crop production. If the cattle eat plastic film, can cause livestock digestive disorders, or even death.In 3, landfill of city garbage treatment in China is still one of the main methods of. Because the plastic film small density, large volume, it can quickly fill the ground, reduce landfill site of garbage disposal capacity of landfill site; and, after because of soft ground, garbage in bacteria, viruses and other harmful material is easy to infiltrate into the ground, groundwater pollution, endanger the surrounding environment.4, if the waste plastic direct incineration, will cause serious environmental pollution two. Plastic incinerator, not only produces a lot of smoke, but will produce dioxin -- so far the most toxic substances. Dioxin into the soil, with at least15 months to gradually break down, it will do harm to plants and crops; dioxin on animal's liver and brain have serious damage. Incineration of waste emissions of dioxin pollution to the environment, has become one of the world's attention as a very sensitive problem.In addition, the disposable plastic tableware degradation, now many city to promote the use of green tableware -- paper tableware paper products, is the principle of composition of cellulose degradation by microorganisms. However, instead of using paper tableware plastic tableware foam is also unwise. First of all, paper tableware will also bring visual pollution. Their degradation speed is not fast, often in a few days or even several months will not complete degradation. Secondly, for paper tableware, in addition to use straw, rice paste, but also to join the1/3 around wood pulp, if the comprehensive promotion, will cause a large number of wood consumption, leading to a rise in deforestation. China's forest coverage rate is only 13.92%, the per capita forest area is equivalent to only17.2% of the world average level. In third, pulp is always the water consumption big, energy-hungry and large discharge. Pulping process requires a large amount of water, and our country belongs to the shortage of water resources in the country. If untreated sewage directly discharged into rivers, water pollution, cause; of paper tableware molded dried immediately, this needs many energy consumption. While China's energy structure with coal as the main fuel, which can increase the content of SO2 in air, caused by acid rain.In three, the prevention and treatment of white pollution1, we should reduce the amount of disposable plastic tableware, paper tableware use. No disposable tableware is not conducive to environmental protection, but also the biggest waste of resources. In our daily life, should not be excessively relying on plastic bags. In the store, can use one or two plastic bags packed commodity classification, the weight of goods in the bag is completely within the tolerance range, some customers are insisting that took more than one or two bags. The majority of consumers to supermarket plastic bag home when the garbage bag is used, discarded after two pollution caused to the environment. Therefore, we should refuse to use plastic bags to buy food or holding food, buy food available food basket or bag to avoid the use of the disposable, reduce the pollution of the environment. While holding food can use their own stainless steel or plastic boxes, sanitation, environmental protection, but not to physical harm.2, recycling of waste plastics and the resource is the fundamental way to solve the white pollution. In fact, plastics and other materials than, have a distinct advantage: the plastic can be recycled repeatedly. Waste plastic recycling, after processing, can become products, or making gasoline and diesel.In recent years, in Germany, Japan, the United States and other countries, because of the importance of packaging material recycling, has achieved the plastic production, use, recycle, reuse of benign loop, fundamentally eliminate the white pollution. In China, recycling of waste plastics work has started. We should cooperate with the relevant government departments, the waste classification, so that recovery can be performed smoothly.3, to strengthen the propaganda of environmental protection, raise the environmental awareness of citizens, in the community formed a good environmental atmosphere, is to solve the white pollution and other forms of pollution premise. For example, to recycling of waste plastics, will implement the recycling packaging system, different types of garbage in different bins, this needs us to have highly conscious awareness of environmental protection.白色污染的资料 一、什么是白色污染 所谓“白色污染”，是人们对塑料垃圾污染环境的一种形象称谓。它是指用聚苯乙烯、聚丙烯、聚氯乙烯等高分子化合物制成的各类生活塑料制品使用后被弃置成为固体废物，由于随意乱丢乱扔，难于降解处理，以致造成城市环境严重污染的现象。 二、白色污染的危害 白色污染存在两种危害：视觉污染和潜在危害。 视觉污染指的是塑料袋、盒、杯、碗等散落在环境中，给人们的视觉带来不良刺激，影响环境的美感。 白色污染的潜在危害则是多方面的。 1、 一次性发泡塑料饭盒和塑料袋盛装食物严重影响我们的身体健康。当温度达到65℃时，一次性发泡塑料餐具中的有害物质将渗入到食物中，会对人的肝脏、肾脏及中枢神经系统等造成损害。 我们现在用来装食物的超薄塑料袋一般是聚氯乙烯塑料。早在四十年前，人们就发现聚氯乙烯塑料中残留有氯乙烯单体。当人们接触氯乙烯后，就会出现手腕、手指浮肿，皮肤硬化等症状，还可能出现脾肿大、肝损伤等症。在我国，我们用的超薄塑料袋几乎都来自废塑料的再利用，是由小企业或家庭作坊生产的。这些生产厂所用原料是废弃塑料桶、盆、一次性针筒等。生产时，首先用机械把原料粉碎成塑料粒子，再把塑料粒子放在一个水池里清洗（名曰消毒），取出来晒干，再用机械把它压成膜，制成各种塑料袋。每次吃饭时，就有不少人用塑料袋装饭菜，他们不知道这种行为不仅危害环境，也危害自己的身体。 2、 使土壤环境恶化，严重影响农作物的生长。我国目前使用的塑料制品的降解时间，通常至少需要200年。农田里的废农膜、塑料袋长期残留在田中，会影响农作物对水分、养分的吸收，抑制农作物的生长发育，造成农作物的减产。若牲畜吃了塑料膜，会引起牲畜的消化道疾病，甚至死亡。 3、 填埋作业仍是我国处理城市垃圾的一个主要方法。由于塑料膜密度小、体积大，它能很快填满场地，降低填埋场地处理垃圾的能力；而且，填埋后的场地由于地基松软，垃圾中的细菌、病毒等有害物质很容易渗入地下，污染地下水，危及周围环境。 4、 若把废塑料直接进行焚烧处理，将给环境造成严重的二次污染。塑料焚烧时，不但产生大量黑烟，而且会产生二恶英——迄今为止毒性最大的一类物质。二恶英进入土壤中，至少需15个月才能逐渐分解，它会危害植物及农作物；二恶英对动物的肝脏及脑有严重的损害作用。焚烧垃圾排放出的二恶英对环境的污染，已经成为全世界关注的一个极敏感的问题。 另外，由于一次性塑料餐具难降解，现在许多城市都推广使用绿色餐具——纸制餐具，原理是纸制品的组成物纤维素能被微生物降解。但是，用纸制餐具代替发泡塑料餐具亦不明智。首先，纸制餐具同样也会带来视觉上的污染。它们的降解速度并不快，往往在几十天甚至几个月内也不会降解彻底。其次，制纸制餐具时，除用到草浆、稻浆外，还要加入1/3左右的木浆，若全面推广，势必造成大量木材的消耗，导致森林砍伐的加剧。而我国森林覆盖率仅为13.92%，人均占有森林面积只相当于世界人均水平的17.2%。第三，制纸浆历来是耗水大户、耗能大户及排污大户。造浆工艺需大量水，而我国属于水资源短缺的国家。若污水未经处理，直接排入河流中，会引起水污染；纸制餐具成型后需立即烘干，这就需要耗大量能。而我国能源结构是以燃煤为主，这样就会增加空气中SO2的含量，引起酸雨。 三、白色污染的防治 1、我们应尽量减少一次性塑料餐具和纸制餐具的使用。任何一次性餐具不仅不利于环保，也是对资源的最大的浪费。我们在日常生活中，不应过度依赖塑料袋。在商店，完全可以用一两个塑料袋分类装好的商品，商品重量也完全在袋子的承受范围之内的，有些顾客却硬是要求多拿一两个袋子。大部分消费者把超市塑料袋带回家中当垃圾袋使用，丢弃后对环境造成二次污染。因此，我们应拒绝使用塑料袋买菜或盛装食物，买菜可用菜篮子或布袋避免使用上的一次性，减少对环境的污染。而盛装食物可以使用自备的不锈钢或塑胶饭盒，既卫生，又环保，还不会对身体造成危害。 2、 回收废塑料并使之资源化是解决白色污染的根本途径。其实，塑料和其它材料比，有一个显著的优点：塑料可以很方便地反复回收使用。废塑料回收后，经过处理，既能重新成为制品，亦可制得汽油与柴油。 近年来，在德、日、美等国家，由于重视对包装材料的回收处理，已经实现了塑料的生产、使用、回收、再利用的良性循环，从根本上消除了白色污染。而在我国，回收废塑料的工作已经起步。我们应配合政府有关部门，把废弃物分类，以便回收工作能顺利地进行。 3、 加强环保宣传，提高公民的环保意识，在社会上形成良好的环保氛围，是解决白色污染及其它各种形式污染的前提。例如，要回收废塑料，就要实行垃圾回收分装制度，把不同类的垃圾放在不同的垃圾桶内，这就需要我们有高度自觉的环保意识。

层状双氢氧化物（简称LDHs）又称水滑石（HT），由于具有独特的层状结构和奇特的性能，添加到聚合物之中，具有环境友好、高效无毒、有效抑烟等优点，其相关研究已成了近几年研究的热点。稀土元素由于具有特殊的电子结构，使其在催化、发光、磁性等领域的应用具有很大的潜力，特别是作为耐火材料添加剂的相关领域的研究受到了广泛重视。从已报道的相关文献来看，一般是以螯合物形式将稀土元素负载到层状双氢氧化物的层间，而直接将稀土元素通过同晶取代置换到LDHs层板上的报道还很少。本论文将采用报道不多，制备简单的微波晶化低饱和共沉淀法，快速制备出一系列含稀土LDHs，考察了掺杂稀土量对LDHs结构的影响，并将其运用到聚合物中研究其对聚合物的阻燃性能、力学性能，抑烟性能等的影响，获得了以下具有创新性的结果。When layered double hydroxides (LDHs), also called hydrotalcites (HT) are added into polymers, they have the advantages of environmental friendly, highly efficient, nontoxic, smoke inhibiting and other properties due to their unique stratified structure and peculiar performance, and this relevant study has become the major focus of researchers in recent years. In view of rare earth elements’ special electronic structures, it has a great application potential in the fields of catalysis, luminescence and magnetism; particularly as an additive to refractory materials, studies in this related field has been attracting extensive attentions. From the perspective of published documentations, generally the rare earth elements are loaded in between the layers of LDHs in the form of chelate complex; there are limited reports on the method of directly replacing rare earth elements on the layers of LDHs by isomorphous substitution. This essay adopts the rarely reported and simple method of microwave crystallized low saturation co-precipitation to quickly prepare a series of LDhs with rare earth contents; as well as investigates the impact on LDHs’ structure by various different quantities of rare earth doping, and applies it to study its effects on polymers in terms of flame retardation, mechanical property, smoke inhibiting property and so on. The following are the creative results obtained: 通过低饱和态共沉淀法，辅助微波手段，制备了系列含稀土Ce和La的LDHs；并通过XRD和FT-IR等对其结构进行了表征，筛选出结晶度高，晶相单一的样品Zn-Al-Ce-LDHs（n(Zn2+)/n(Al3+)=x，n(Ce4+)/n(Al3+)=y），将其用于聚丙烯（PP）中，考察了复合材料的阻燃性能。当Zn-Al-Ce-LDHs添加量为10%时，将PP的极限氧指数由17.4%提高到42%，而且随着添加量的提高，极限氧指数也随之升高，与添加量呈线性关系。当Zn-Al-Ce-LDHs添加量为50%时，PP的极限氧指数可达到58%，说明Zn-Al-Ce-LDHs能有效地提高复合材料的阻燃性能。A series of LDHs with cerium and lanthanum were prepared by low saturation co-precipitation assisted by microwave means, and by characterizing their structures with X-ray diffraction and FT-Infrared spectroscopy, high crystalline, single crystal phase samples of Zn-Al-Ce-LDHs were selected. [(n(Zn2+)/n(Al3+)=x，n(Ce4+)/n(Al3+)=y)]. Then they were applied to Polypropylene (PP) and the flame retardant property of the composite materials was investigated. When the addition of Zn-Al-Ce-LDHs was 10%, the limited oxygen index of PP was elevated from 17.4% to 42%, and the index kept on rising as the amount of addition was increased, indicating a linear relationship with the amount of addition. When the addition of Zn-Al-Ce-LDHs was 50%, the limited oxygen index of PP could reach 58%, this showed that Zn-Al-Ce-LDHs can effectively improve the flame retardant property of the composite materials.采用不同类型的LDHs、在复合材料中保持相同的添加量，研究了LDHs/PP复合材料的热稳定性，结果表明：在低温段，Zn-Al-Ce-LDHs能有效的延缓复合材料的热降解的反应的发生；在高温段，Zn-Al-Ce-LDHs/PP的残炭量明显高于Mg-Al-LDHs/PP、Mg-Al-Ce-LDHs/PP，说明Zn-Al-Ce-LDHs具有明显的促进复合材料成炭的效果。在采用相同Zn-Al-Ce-LDHs、不同LDHs添加量的复合材料中，复合材料的热稳定性和残炭率仅与添加量有关，且残炭量与添加量基本呈线性关系。The thermal stability of LDHs/PP composite materials was studied by adopting different types of LDHs with similar amount of addition to the composite materials; the result had shown that at the low temperature range, Zn-Al-Ce-LDHs could effectively delay the composite materials’ reaction to thermal degradation; while at the high temperature range, the char residue of Zn-Al-Ce-LDHs/PP was significantly more than that of Mg-Al-LDHs/PP and Mg-Al-Ce-LDHs/PP; this explained the distinct effect of Zn-Al-Ce-LDHs in promoting char formation of the composite materials. When adopting similar Zn-Al-Ce-LDHs with different amounts of addition, the thermal stability and char residue of the composite materials were only relative to the amounts of addition, and the char residue and the additions basically showed a linear relationship. 将Zn-Al-Ce-LDHs与EVA进行熔融混合制备成复合材料，对其进行极限氧指数以及锥形量热等燃烧性能测试，结果表明：当Zn-Al-Ce-LDHs的添加量少于40%时，对复合材料的阻燃性提高不明显，但是超过40%时，对复合材料的阻燃性有了大幅度的提高，同时，复合材料的热释放速率和烟释放速率随着Zn-Al-Ce-LDHs添加量的升高而降低，说明Zn-Al-Ce-LDHs对EVA材料的燃烧和发烟具有明显的抑制作用。对复合材料进行热重分析，结果表明：Zn-Al-Ce-LDHs可以有效延缓EVA材料的热分解，并可促进EVA材料的成炭作用，复合材料的热稳定性与Zn-Al-Ce-LDHs的添加量具有线性关系。A composite material was prepared by melt compounding Zn-Al-Ce-LDHs with EVA, and flammability testing such as limited oxygen index and cone calorimetry was conducted; the results had shown that when the amount of Zn-Al-Ce-LDHs addition was less than 40%, there was no obvious enhancement of flame retardant property of the composite material; but when exceeding 40%, the flame retardant property of the composite material increased remarkably; at the same time, the heat and smoke emission rates of the composite material decreased as the addition of Zn-Al-Ce-LDHs was increased; this explained that Zn-Al-Ce-LDHs had a significant inhibiting function on the combustion and fuming of EVA materials. The results of thermogravimetric analysis conducted on the composite material had shown that Zn-Al-Ce-LDHs could effectively delay the thermal degradation of EVA material and promote its char formation function; it was also noted that the thermal stability of composite materials and the amount of addition of Zn-Al-Ce-LDHs had a linear relationship. 【英语牛人团】

Layered double hydroxides (referred to as LDHs), also known as hydrotalcite (HT), because of the unique layered structure and the peculiar properties of being added to the polymer, environmentally friendly, efficient non-toxic, effective smoke suppression, etc. Its research has become a research hotspot in recent years. REE as a special electronic structure, so in catalysis, luminescence, magnetic and other fields of application has great potential, especially as related to the field of refractory additives research has been extensive attention. From the reported literature, the general form of chelates of rare earth elements is loaded into the layered double hydroxide layer, but directly to the rare earth elements replaced by isomorphous replacement to report is still on the shelves LDHs less. The paper reported that not much will be used to prepare simple and low in saturated microwave precipitation crystallization, rapid preparation of a series of rare earth containing LDHs, examined the amount of doped LDHs structure and apply it to study polymer The flame retardancy of polymers, mechanical properties, the impact of smoke suppression performance, etc., to obtain the following innovative results. Low saturation state by co-precipitation method, microwave assisted method to prepare a series of Ce and La rare earth containing the LDHs; and through the XRD and FT-IR to characterize its structure, etc., selected high crystallinity samples of single crystal Zn -Al-Ce-LDHs (n (Zn2 +) / n (Al3 +) = x, n (Ce4 +) / n (Al3 +) = y), be used in polypropylene (PP), the investigated composite flame retardant performance. When the Zn-Al-Ce-LDHs 10% addition level, the PP LOI from 17.4% to 42%, and with the addition of improved, limiting oxygen index also will be increased, and amount was linear relationship. When the Zn-Al-Ce-LDHs 50% addition level, PP LOI up to 58%, indicating that Zn-Al-Ce-LDHs can effectively improve the flame retardancy of the composite. Different types of LDHs, in the composite to maintain the same dosage, of the LDHs / PP composites thermal stability, the results show that: in the low-temperature, Zn-Al-Ce-LDHs can effectively delay the composite thermal degradation reactions; at a high temperature section, Zn-Al-Ce-LDHs/PP the residual carbon was significantly higher than Mg-Al-LDHs/PP, Mg-Al-Ce-LDHs/PP, that Zn-Al-Ce -LDHs obviously promote carbon composite materials into effect. In the same Zn-Al-Ce-LDHs, addition of different LDHs composite materials, composite materials, thermal stability and char rate and amount of relevant, and the amount of residual carbon content and adding a linear relationship. The Zn-Al-Ce-LDHs and EVA were prepared by melt mixed composites, its limiting oxygen index and cone calorimeter combustion properties such as test results show that: when the Zn-Al-Ce-LDHs to add less than 40%, the flame retardancy of the composites increase was not obvious, but more than 40%, the flame resistance of composite materials have increased significantly, while the composite heat release rate and smoke release rate with the Zn -Al-Ce-LDHs are increasing the amount added, indicating that Zn-Al-Ce-LDHs on the EVA and smoke of burning material significantly inhibited. The composite thermal gravimetric analysis results showed that: Zn-Al-Ce-LDHs can effectively delay the thermal decomposition of EVA, and promote the role of EVA material into carbon composite thermal stability and Zn-Al-Ce- LDHs of the addition of a linear relationship.

Layered double hydroxides LDHs) and (hereinafter called water talc (HT), due to its unique layered structure and peculiar properties, add to polymer in, with environmental friendly and efficient non-toxic, effective smoke suppression etc, and its relevant research has become the hotspot in recent years. Rare earth elements has special electronic structure due, so that in the catalytic, glow, the application of magnetic fields has great potential, especially as fire-proof material additives research in the field of the relevant by extensive attention. From the perspective of relative literatures have been reported, the general is chelates form will load to rare earth elements layered double hydroxides, and between layers of the rare earth elements directly with crystal replace replacement by LDHs plate to the reports were rare. This paper will be few, simple preparation by reports of microwave crystallization precipitation, low saturation were a series of quick preparation containing rare earth doped LDHs, examines the rare earth amount of influence of the structure of LDHs, and was applied to study the polymer of polymer retarding properties, mechanical properties, smoke suppression performance under the influence of innovative, obtained the results.Through the low saturation state total precipitation, assisted microwave method, the preparation of a series of rare earth Ce and the La containing LDHs; And by XRD and ft-series IR on the structures were characterized by high crystallinity, and crystalling phase single sample Zn - Al - Ce - LDHs (n (Zn2 +) / n (Al3 +) = x, n (Ce4 +) / n (Al3 +) = y), it will be used for polypropylene (PP), investigates the flame retardant properties of composite materials. When Zn - Al - Ce - adding amount of LDHs 10% for the limits of the PP, will by the oxygen index increased to 42% 17.4, and with the additive quantity increased, limit the oxygen index also increase, a linear relationship with additives. When Zn - Al - Ce - adding amount of LDHs for 50%, the PP limit the oxygen index can achieve 58%, Zn - that Al - Ce - LDHs can effectively improve the composite flame retardant properties.Using different types of LDHs, keep the same in composite materials, adding amount of LDHs/PP composite materials, the results show that the thermal stability in low temperature section, Zn, Al - Ce - - LDHs can effectively slowing of composite degradation the occurrence of the reaction heat; In high temperature section, Zn - Al - Ce - LDHs/PP amount of carbon residue significantly higher than Mg - LDHs/PP Al -, Mg - Al - Ce - LDHs/PP, Zn - that Al - Ce - LDHs has obviously promote the effect of peat-forming composite materials. In using the same Al - Ce - Zn - adding amount of LDHs LDHs, different of composite material, composite thermal stability and carbon residue with rate only adding amount of relevant and carbon residue quantity with the linear adding amount of basic.Will Zn - LDHs Al - Ce - with EVA to melt into composite materials, mixed preparation of its limit the oxygen index and tapered quantity heat and so on combustion performance test, the result shows that: when Zn - of LDHs Al - Ce - adding amount of less than 40% when, the flame retardancy of composite materials increase is not clear, but more than 40% when, the flame retardancy of composite materials have greatly improved, meanwhile, composite material heat release rate and smoke release rate as Zn - Al - Ce - adding amount of LDHs, explain the rise and reduce Zn - LDHs Al - Ce - to EVA material combustion and hair yanju have obvious inhibition. To compound materials for thermogravimetric analysis, the result shows: Zn - Al - Ce - LDHs can effectively relieve EVA material, and can promote the thermal decomposition of EVA material peat-forming role, composite thermal stability and Zn - Al - Ce - add LDHs measuring cable sex.