Polyvinyl chloride fibres

The outstanding property of these fibres is the shrinkage on heating which enables the manufacture of various specialty products. The fabric can be heat-set by 

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For blended fabrics with cellulosic fibres it is possible to produce heat-embossed blend fabrics with 25% polyvinyl chloride fibres. Heat treatment is carried out by one passage on pin-stenter without overfeed at 85-90 C, and if for example a 15-17% shrinkage is to be achieved, the speed of travel is about 10 m/min. 

The use of coatings applied in the form of tape is also increasing. Polyethylene and polyvinyl chloride films, either self adhesive or else supporting films of butyl adhesive, petrolatum or butyl mastic are in use as materials applied cold at ambient temperatures. Woven glass fibre or nylon bandage is also used to support films of filled asphalt or coal tar and these are softened by propane gas torches and applied to the steel surface hot, cooling to form a thick conforming adherent layer. 

Before World War II, German developed a synthetic fibre from polyvinyl chloride. In America, a copolymer of vinyl chloride and vinyl acetate was marketed as Vinyon . Dow chemical marketed as Saran a copolymer from vinylidene chloride and vinyl chloride. Saran fibre is characterised by its remarkable resistance of most of chemical reagents and fire. 

Many of the remarks made in the previous section concerning fibres can be applied to the analysis of plastics. Some polymers are soluble in organic solvents and samples may be prepared for direct aspiration into a flame in this way, e.g. MIBK is a suitable solvent for polyesters, polystyrene, polysiloxanes, cellulose acetate and butyrate dimethyl formamide for polyacrylonitrile, dimethyl acetamide for polycarbonates and polyvinyl chloride cyclohexanone for polyvinyl chloride and polyvinyl acetate formic acid for polyamides and methanol for polyethers. These organic solutions may alternatively be injected into a graphite furnace. Otherwise, polymers may be wet or dry ashed and the resultant ash dissolved in acid. An approach which is attracting increasing interest is the direct insertion of solid samples into a graphite furnace. 

Polyvinyl chloride, alcohol, acetate, and their copolymers are used to a limited extent for fibre production. They are cheap because the monomers are easily prepared from ethylene or acetylene, both of which are available in abundance. The fibres have not been used much for textiles, however, because they soften at temperatures varying between 50 and 100°C, according to the composition of the polymer. 

Pure polyvinyl chloride is the composition of PCU, produced in Germany, and of Rhovyl and Thermovyl, made in France. PCU loses its mechanical stability and shrinks considerably, due to the stretched molecules resuming their original configurations, at temperatures of 75 to 80 C. It compares unfavourably, therefore, with other synthetic fibres for textile uses. It has found certain specialized applications for making fishing lines, filter cloths, and sails. 

In order to determine the sources of contamination, some water samples, including wastewaters and effluents from different industries, were also taken. Along the Cinca River and in the industrial area of Monzon, industrial effluents from two different industries were selected the first one produced EPS (expandable polystyrene) treated with flame retardants and ABS (acrylonitrile-butadiene-styrene), and the second one produced PVC (polyvinyl chloride). As regards the Vero River, three industries were sampled the first one was a textile industry which produced polyester fibres treated with flame retardants, the second produced epoxy resins, and the third focused on polyamide polymerisation. 

AGM — membrane sandwich. The combination of a membrane with an AGM separator has been investigated with a view towards controlling the oxygen transport as well as improving the compressive properties of the separator. With reference to the latter aspect, a AGM-membrane sandwich has been evaluated [19]. The AGM consisted of 100% fine fibres, and the incompressible polymer membrane was a mixture of polyvinyl chloride and 5-10 wt.% silica, which was partly extracted to increase the pore size and porosity. The properties of the two separator components are summarized in Table 7.9 [22]. 

Thermal welding is confined to fabrics that have high thermoplastic synthetic fibre content such as nylon, polyester, polypropylene, acrylic, and certain fibre blends. As a general mle, the textiles to be welded must be made of the same thermoplastic or be physically and chemically compatible with one another. Fabrics that have a thermoplastic coating (e.g., polyvinyl chloride, PU, and polypropylene) are also amenable to thermal-welding processes, since in these cases the coating acts as the adhesive. Weldability will vary with the type of material, its thickness, and its form (coating, film, fibre). 

This document focuses on the main products of the European polymer industry both in production figures and in environmental impact, mainly produced in dedicated installations for the production of one specific polymer. The list of products covered is not conclusive but includes polyolefins, polystyrene, polyvinyl chloride, unsatuiated polyesters, emulsion polymerised styrene butadiene rubbers, solution polymerised rubbers containing butadiene, polyamides, polyethylene terephthalate fibres and viscose fibres. 

The flexible, tubular hner of a CIPP is typically made of polyester fabric that is a needled, woven or knitted reinforced fibre sheet using carbon, glass or aramid fibres or a combination of both. Depending on its application, the hner is coated with an impervious film such as polyethylene for the transport of drinking water or polyester for gas pipes. Other coatings include urethane and polyvinyl chloride (PVC). The final smooth surface reduces the surface friction and provides an additional corrosion barrier for the pipe. Liner tube sizes range from 100 to 2500 mm in diameter with... 

Most vinyl acetate is converted into polyvinyl acetate (PVA) which is used in the manufacture of dispersions for paints and binders and as a raw material for paints. It is also copolymerized with vinyl chloride and ethylene and to a lesser extent with acrylic esters. A substantial proportion of vinyl acetate is converted into polyvinyl alcohol by saponification or transesterification of polyvinyl acetate. The main applications for polyvinyl alcohol are either as raw material for adhesives or for fibres. It is also employed in textile finishing and paper glueing, and as a dispersion agent (protective colloid). The world production capacity of PVA was 4.35 Mt/a in 2005, of which 2.1 Mt were converted into polyvinyl alcohol. 

Figure 4.4 Effect of sodium chloride (NaCl) in the polyvinyl alcohol (PVAL) solution on fibre morphology (voltage = 5kV, tip-target distance = 10 cm flow rate = 0.2 ml/h). Concentration of NaCl solution in water (a) 0.05 vol% (b) 0.10 vol% (c) 0.15 vol% and (d) 0.20 vol%...

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