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PVC materials

Following the success in blending rubbery materials into polystyrene, styrene-acrylonitrile and PVC materials to produce tough thermoplastics the concept has been used to produce high-impact PMMA-type moulding compounds. These are two-phase materials in which the glassy phase consists of poly(methyl methacrylate) and the rubbery phase an acrylate polymer, usually poly(butyl acrylate Commercial materials of the type include Diakon MX (ICI), Oroglas... [Pg.413]

A series of polyester-based TPU (566TPU series) were synthesized in our lab and used to blend with PVC to manufacture a modified PVC material for medical uses [14]. Morphological studies showed that 566TPU has very good compatibility with PVC. Detailed mechanical and electronic property tests were also conducted. Some of the data are provided in Tables 3 and 4. [Pg.143]

These data show that the 566TPU/PVC polymeric blend has good mechanical properties, especially at low temperatures. Other tests showed very good oil resistance of this material. Also, the migration rate of plasticizer is only one-fourth of that of commercial medical grade flexible PVC material. [Pg.143]

There are several ways in which the impact properties of plastics can be improved if the material selected does not have sufficient impact strength. One method is by altering the composition of the material so that it is no longer a glassy plastic at the operating temperature of the product (Chapter 6). In the case of PVC this is done by the addition of an impact modifier which can be a compatible plastic such as an acrylic or a nitrile rubber. The addition of such a material lowers the glass transition temperature and the material becomes a rubbery viscoelastic plastic with much improved impact properties. This is one of the methods in which PVC materials are made to exhibit superior impact properties. [Pg.92]

A great variety of PVC materials have been tested in the process thus far cable, cable trays, flooring material, window frames, artificial leather, packaging, pipes, flexible hoses, ring binders and roofing material. This indicates that the process is robust and can handle a broad range of PVC materials. In terms of chlorine content, there are no restrictions. With the completion of the pretreatment pilot plant, the contents of other plastics and metals may now be reduced significantly. [Pg.17]

In the framework of the phthalate controversy Wilkinson and Lamb [109] used various in vitro methods in which known amounts of soft PVC materials were shaken, stirred, impacted, or otherwise mechanically agitated in some type of simulated saliva under controlled conditions (T, f), and the saliva extracted into hexane for analysis. Shaking-flask (liquid-liquid) extraction was also used for the solvent extraction of nonionic surfactants of the general type R0(CH2CH20) H (where R... [Pg.66]

The PVC materials used in these experiments were rigid. [Pg.523]

A few recent events make it particularly interesting to valuate the fire hazard resulting from the burning of PVC materials, when they are present in a plenum. These include the recent regulations promulgated in New York State regarding the creation of a data base for smoke... [Pg.595]

Certain dioctyltin compounds are used for clear PVC materials. Dialkyltin carboxylate and dialkyltin mercaptide heat stabilizers are used in the PVC industry in many application34. [Pg.884]

PVC materials are often defined to contain 50% or more vinyl chloride units by weight. PVC is generally a mixture of a number of additives and often other units, such as ethylene, propylene, vinylidene chloride, and vinyl acetate. Structurally similar products, but with differing properties, are made from the chlorination of PE but almost all PVC is made from the polymerization of vinyl chloride. Typical homopolymers are about 400-1000 units long. [Pg.195]

Tacticity of the PVC varies according to the particular reaction conditions but generally manufactures favor a syndiotactic form with many PVC materials being about 50%i sPVC. The reported amount of crystallinity is in the range of 5%i-10%i. This allows for a material with some strength, but one with sufficient amorphous regions to retain good flexibility. [Pg.195]

Polyvinyl chloride is processed into a number of forms by including additives. Additives are used to vary the properties of PVC so that it can be made soft and flexible or hard and rigid. Additives are also used to inhibit decomposition as a result of exposure to sunlight, ozone, and chemicals. Plasticizers are the primary additive included in PVC materials. Di(2-ethylhexyl) phthalate (DEHP) and a host of other phthalates are the most common plasticizers. Plasticizers impart flexibility, thermal stability, strength, and resilience to PVC compounds. PVCs without plasticizers are classified as UPVC the letters stand for unplasticized polyvinyl chloride. UPVC is rigid and used for conduit, containers, gutters, and floor tiles. Other common PVC additives are biocides, lubricants, and pigments. [Pg.296]

Un-vulcanized CSM/PVC material (chloro sulphonated polyethylene/polyvinyl chloride blend) for autoclave or hot-air vulcanization applied with the two-layer adhesive system. [Pg.59]

Photooxidation Diffusion Chemical changes due to photochemical reactions Introduction of contaminants from man-made materials, such as solvents from polyvinyl chloride (PVC) materials and PVC cement, plasticizers, and phthalates from polyethylene and polypropylene materials Protection from exposure to light, use of amber glass bottles Use of inert materials (PTFE, fiberglass-reinforced epoxy materials) steam-cleaning of groundwater well components prior to installation... [Pg.137]

Hirschler, M.M., Toxicity of the smoke from PVC materials New concepts, Prog. Rubber Plast. Technol.,... [Pg.662]

Three electrode types are used. The first is a partly smooth surface to allow minimum contact with the test atmosphere. The second is corrugated to enhance the contact and facilitate HC1 escape. The third is hollow on the bottom for placing powdered materials and has a corresponding projection on the upper part (Figure 5). PVC materials in the shape of powder and paste foils can be evaluated in the apparatus... [Pg.65]

To determine the color change of PVC materials, another device has been built and tested, as shown in Figure 6. The basic apparatus is a... [Pg.65]

Accordingly, the degree of polymerisation of the degraded polymer is not decreased, but a deeply red to violet coloured PVC material is obtained... [Pg.771]

PVC has been under scrutiny in landfill immersion due to perceptions about the leaching of additives, in particular, heavy metals and phthalates (282). A study has shown that no degradation of the PVC occurred (252). However, the viewpoint that PVC materials should be buried in landfill in preference to being recycled is not generally accepted (422). [Pg.12]

Trials are carried out and described, which proves the method of elastic-deformation dispersion as a technique in making possible the effective processing of waste from various PVC materials to obtain fine-particle recycled product with wide possibilities of practical use. The elastic-deformation dispersion method, is based on the idea of multiple breakdown, when the material is subjected to the combined action of high pressure and shear deformation at elevated temperatures. Elastic-deformation dispersion of roughly ground materials with particle diameter of 1-3 cms. was carried out in a single-... [Pg.56]

Also, the impact on the environment in the pyrolysis of waste plastics must be taken into consideration. If a PVC material is contained in the reactant, the hydrochloric acid is evolved during decomposition of PVC which causes air pollution. Thus, a system is needed... [Pg.135]

One example of waste plastics accepted is shown in Table 26.6. The composition of waste plastic flnff varies enormously and the accepted valne is an average of three samples. PET and PVC materials are predominant, thongh PET bottles are removed by hand-picking in the pretreatment by Niigata city. [Pg.673]

The main route of occupational exposure to vinyl chloride is by inhalation that can occur in plastics manufacturing plants. Inhalation exposure to the general public is generally quite limited and probably restricted to accidental releases from hazardous waste sites and landfills. Vinyl chloride has been detected in surface and well waters, sediment and soil samples near manufacturing facilities. Some dietary exposure can occur from leaching from certain PVC materials into packaged foodstuffs. [Pg.2829]


See other pages where PVC materials is mentioned: [Pg.244]    [Pg.360]    [Pg.880]    [Pg.137]    [Pg.137]    [Pg.93]    [Pg.794]    [Pg.370]    [Pg.271]    [Pg.39]    [Pg.78]    [Pg.195]    [Pg.54]    [Pg.98]    [Pg.93]    [Pg.297]    [Pg.401]    [Pg.228]    [Pg.789]    [Pg.70]    [Pg.299]    [Pg.24]    [Pg.46]    [Pg.91]    [Pg.133]    [Pg.137]    [Pg.667]   
See also in sourсe #XX -- [ Pg.137 ]




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Plasticised PVC materials

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