Polyvinyl chloride network

In terms of tonnage the bulk of plastics produced are thermoplastics, a group which includes polyethylene, polyvinyl chloride (p.v.c.), the nylons, polycarbonates and cellulose acetate. There is however a second class of materials, the thermosetting plastics. They are supplied by the manufacturer either as long-chain molecules, similar to a typical thermoplastic molecule or as rather small branched molecules. They are shaped and then subjected to either heat or chemical reaction, or both, in such a way that the molecules link one with another to form a cross-linked network (Fig. 18.6). As the molecules are now interconnected they can no longer slide extensively one past the other and the material has set, cured or cross linked. Plastics materials behaving in this way are spoken of as thermosetting plastics, a term which is now used to include those materials which can in fact cross link with suitable catalysts at room temperature. 

In this section we demonstrate the performance of the proposed model on an industrial-scale case study. Instead of considering the full scale petrochemical network which may have limited application, we consider a special case of the integration problem. Although the proposed formulation covers the full scale refinery network and petrochemical systems, the case study will consider the integration of a petrochemical complex for the production of polyvinyl chloride (PVC) with a multi-refinery network. PVC is one of the major ethylene derivatives that has many important applications and uses, including pipe fittings, automobile bumpers, toys, bottles and many others (Rudd et al., 1981). 

An important conclusion emerging from these studies is that polyvinyl chloride has a three-dimensional network structure where microcrystallites are believed to... 

In conclusion, we may state that viscoelastic data presented in this paper further reaffirm the contention that polyvinyl chloride has a network structure with microcrystallites acting as cross-links. Incorporation of plasticizer affected PVC in a way similar to amorphous polymers mainly by lowering Tg of the amo-rophous regions. Microcrystallites appear to be stable even in the presence of... 

Which of the following are usually used as network, erosslinked polymers Polypropylene, Polystyrene, Polyvinyl Chloride, Nylon, Epoxy Resins, Phenol-Methanal Polymers, or Polymeric Liquid Crystals ... 

Thornton J (2002) Environmental impacts of polyvinyl chloride building materials. Healthy building network. Available http //wwwliealthybuilding.nel/pvc/ Thomton Enviro Impacts of PVC.pdf. Acessed 2012 May 25. 

Plastic is a material that can be plasticized into certain shapes under certain conditions (temperature, pressure, etc.) and can keep its shape unchanged at room temperature and normal atmosphere pressure. According to their performance after heat treatment, plastics can be divided into thermoplastic and thermosetting plastics. A thermoplastic plastic is generally a linear or branched polymer. It melts when heated and solidifies when cooled, and this kind of behavior can be repeated, so the plastic can be used multiple times. The main varieties are polyethylene, polypropylene, polyvinyl chloride, polystyrene, and acrylonitrile-butadiene-styrene terpolymer. Thermosetting plastic is a space network polymer, which is formed by direct polymerization of monomers or by cross-linking of linear prepolymers. Once the solidification is finished, the polymer cannot be heated back to the plasticizing state. The main varieties are phenolic resin, epoxy resin, amino resin, and unsaturated polyester. 

For a polymer with a low level of crystallinity such as polyvinyl chloride, there is quite extensive swelling (in polar solvents) and a rubbery plasticized material is obtained, which is held together by a crystalline network (see Section 3.11)... 

Some polymers are linear, consisting of a long chain of connected monomers. Polyethylene, polyvinyl chloride, nylon 66 and polymethyl methacrylate are some linear commercial examples that can found in this book. Branched polymers can be visualized as a linear polymer with side chains of the same polymer attached to the main polymer chain. While the branches may in turn be branched, they do not connect to another polymer chain. The ends of the branches are not connected to another chain. In a cross-linked polymer, (also called network polymer), different chains are connected. Essentially, the branches are connected to different polymer chains on the ends. These three polymer structures are shown in Figure 1.3. 

An automated electronic tongue consisting of an array of potentiometric sensors and an artificial neural network (ANN) was developed to resolve mixtures of anionic surfactants. The sensor array was formed by five different flow-through sensors for anionic surfactants, based on polyvinyl chloride membranes having cross-sensitivity features. 

Upon mixing and subsequent hardening a three-dimensional polymeric network develops within the material, which is intimately combined with the three-dimensional stracture of the hardened cement paste. A variety of polymer dispersions may be combined with inorganic cements, as long as the polymeric material is sufficiently resistant to sustain the high-pH enviromnent of the cement paste. These may be thermoplasts, such as polyvinyl acetate, polyvirtyl chloride or polyacrylate thermosets, such as epoxides, polyesters, or polyurethanes and also elastomers, such as natural rabber latex or a butadiene-styrene copolymer. Polymer additions between 5% and 20% may be considered typical. 

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