Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

The most important plastics

Apart from MPW and PVC, several feedstock recycling processes have been developed for some specific plastics. In this respect, the most important plastics are ... [Pg.17]

By far the most important plastic is polyethylene terephthalate (PET). Bottles of this material are formed in a two-stage process. So-called pre-forms are made by injection moulding and, in a second process, are then stretch-blow-moulded to produce a bottle. PET has properties surprisingly like those of glass, but it does not have the same disadvantages of weight and brittleness. [Pg.13]

In terms of consumption, poly(vinyl chloride) (PVC) is one of the most important plastic materials available today, providing unmatched material properties in many applications. Phthalate esters have been used as plasticizers to prepare flexible PVC products since the 1920s [1]. In recent years... [Pg.160]

This figure does not include 2-ethylhexa-nol. n-Butyraldehyde-denved 2-ethylhexa-nol is by far the most important plasticizer alcohol, with an estimated worldwide consumption of 2.4 million t. [Pg.408]

The search for materials to aid in the defense effort during World War II resulted in a profound impetus for research into new plastics. Polyethylene, now one of the most important plastics in the world, was developed because of the wartime need for better-quality insulating materials for such applications as radar cable. Thermosetting polyester resins (now used for boatbuilding) were developed for military use. The terpolymer acrylonitrile-butadiene-styrene (ABS), (telephone handsets, luggage. [Pg.14]

Among the many solvents for plastics, the most widely used are toluene, tetrahydrofuran, dimethylformamide, diethyl ether, acetone, and formic acid. In certain cases, chloroethylene, ethyl acetate, ethanol, and water are also useful. It should he noted that the flammability and toxicity of many solvents requires special care In handling. Benzene should be avoided as much as possible. Tables 3.1 and 3.2 show a compilation of the behaviors of the most important plastics in various solvents. For the systematic analysis of plastics, the distinction between soluble and insoluble polymers provides the first separation into two groups. One can then apply chemical methods to investigate these two groups further. [Pg.28]

If more accurate methods for the determination of the density are not available, immerse the sample in methanol (density, p, at 20 °C = 0.79 g/cm ), water (p=lg/cm ), saturated aqueous magnesium chloride solution (p = 1.34 g/cm ), or saturated aqueous zinc chloride solution (p = 2.01 g/ cm ). Then observe whether the sample stays on the surface of the liquid, floats inside it, or sinks. Its behavior indicates whether it has a lower or a higher density than the liquid in which it is immersed. Table 3.3 contains the densities of the most important plastics (of course, there can be variations). [Pg.32]

Depending on the reaction of the escaping vapors with litmus, it is possible to distinguish three different groups acidic (the litmus paper turns red), neutral (no color change), or basic (the litmus paper turns blue). The pH paper is somewhat more sensitive. Table 3.4 shows the reactions of the decomposition products of the most important plastics. Depending on their... [Pg.36]

A compilation of the most important plastics containing heteroatoms is... [Pg.48]

On the basis of the screening tests described in previous chapters and with the use of certain specific reactions, the most important plastics can be identified through simple separation procedures. Test first for heteroatoms (Chapter 4), and then for solubility in different solvents (Section 3.1). If necessary, test for other characteristic physical properties or carry out chemical reactions. [Pg.50]

Table 4.7 Annual world production and recycling codes of the most important plastics... Table 4.7 Annual world production and recycling codes of the most important plastics...
One of the most important plastics is HIPS. This is a styrene matrix that is imbedded with an impact modifier, which is basically a rubber-like polymer such as polybutadiene. This is shown in Figure 2.52. [Pg.66]

As it is known, the work of fracture U, characterizing expenditure of energy on material deformation up to failure, is one of the most important plasticity characteristics. In paper [5] it was shown, that the fracture character of solids is determined by the fractal dimension df of their structure at 4-2. 50 brittle fracture is realized, at 4 2.50-2.67 - quasibrittle (quasiductile) fracture and at 4 2.70 - ductile fracture. This classification allows to suppose plasticity increase characterized by value U at raising df. Actually, the dependence U dj) shown in Fig. 3 confirms this assumption. This dependence is linear, the increase U is observed at raising df and zero value U is reached at 4=2.50, i.e., at brittle fracture. Since limiting (maximal) value df for real solid is equal to 2.95 then this allows to estimate... [Pg.30]

This process is used by Nan Ya Plastics Corporation to produce, starting from an isomer mixture of octene the alcohol, INA and has a capacity >100 000 mt/a. After 2-EH, INA is the most important plasticizer alcohol, which is a complex mixture of linear and branched Cg alcohols. The most important plasticizer produced from it is diisononyl phthalate (DINP). The raw material sources can be, for example, a Cg fraction from the extraction of Fluid Catalytic Cracking (FCC) C -based polygas, the product of dimerization of butene from a raffinate-2 fraction using the octol or dimersol process, or diisobutylene from the dimerization of isobutylene from raffinate-1. [Pg.678]

This chapter will discuss the various methods that have been developed between 1940 and 2010 to manufacture polyethylene in a cost-effective manner to become the most important plastic material in use today. [Pg.225]

A report published in 1943, mentioned that as many as 20,000 different chemicals had been proposed or tested as plasticizers [5], Based on that number, it is expected that today, 70 years after the publication of that report, the total number of chemicals that have been described or proposed to have potential usage as plasticizers may approach 30,000. Of this huge number, only about 100-150 are based on phthalate esters, which means that the overwhelming majority of these proposed plasticizers are nonphthalate plasticizers. The reasons that phthalates developed as the most important plasticizers are that none of the other alternatives were able to match the performance, lower costs, exceptional quality, and supply positions that can be achieved with phthalate esters. [Pg.534]


See other pages where The most important plastics is mentioned: [Pg.326]    [Pg.933]    [Pg.259]    [Pg.304]    [Pg.360]    [Pg.326]    [Pg.15]    [Pg.23]    [Pg.72]    [Pg.936]    [Pg.110]    [Pg.289]    [Pg.38]    [Pg.40]    [Pg.195]    [Pg.560]    [Pg.353]    [Pg.962]    [Pg.7]    [Pg.562]    [Pg.533]    [Pg.541]    [Pg.416]    [Pg.183]   


SEARCH



Important Plastics

© 2024 chempedia.info