Transparent articles

Dyes are miscible with the polymer and hence do not have dispersion problems. They include many of the dyes that have been developed for dying fibres, e.g., azo and anthroquinone derivatives. They are particularly useful for transparent articles, e.g., automotive taillights, decorative film. They can be added either as a dry powder or as a colour concentrate (requiring 10-fold dilution). 

Although PBT has many desirable properties, its rapid crystallization almost always renders it opaque. While transparent PET products are quite common, PBT crystallization can rarely be quenched to the extent necessary for the formation of transparent articles. Thin films of PBT are translucent, allowing some light to penetrate, but are almost never clear. 

ALLYL ESTER RESINS. The allyl radical (CH2CH=CH2) is the basis of the allyl family of resins. Allyl esters arc based on monobasic and dibasic acids and are available as low-viscosity monomers and thermoplastic prepolymers. They are used as crosslinking agents for unsaluraied polyester resins and in the preparation of reinforced thermoset molding compounds and high-performance transparent articles. All modem thermoset techniques may be used for processing allyl resins. 

Polystyrene may be extruded to produce film and other transparent articles with high gloss finish but in commercial practice the formulations toughened with rubber are used to a greater extent (extruded transparent film is toughened by stretching and orientation while it is still hot from the die). 

Methylene chloride, ethylene dichloride, and trichloroethylene are some of the fast-drying solvents that produce strong joints. However, they are unsatisfactory for transparent articles of polystyrene because they cause rapid crazing. Medium-drying solvents such as toluene, perchloroethylene, and ethyl benzene that have higher boiling temperature are less apt to cause crazing. 

S. L. Schmidt, B. Lynch, and A. S. Agrawal. Process for making PEN/PET blends and transparent articles therefrom. US Patent 6 586 558, assigned to Continental PET Technologies, Inc. (Florence, KY), July 1,2003. 

A production of transparent articles from polysulfone required addition of plasticizer to polysulfone that was specially purified to remove certain reaction impurities. Plasticizer is added to improve film flexibility. Plasticizers having high compatibility with polysulfone include diethyl phthalate, benzyl butyl phthalate, tricresyl phosphate, and methyl phthalyl ethyl glycolate. Up to 30 wt% of plasticizer can be used but usually 10 wt% of plasticizer is added. ... 

One drawback of antimony trioxide is its pigmenting effect even in coloured grades it can not be used at all for transparent articles. 

Polystyrene Mass-produced transparent articles, thermoformed packaging, etc. Thermal insulation (foamed), etc... 

Sanitized AG has developed Sanitized Silver, which uses a transparent glass ceramic carrier, requires a relatively low dose level, has good high-temperature resistance and is said not to affect the appearance of transparent plastics by dulling them. It has been granted FDA approval for food contact. Ciba Specialty Chemicals has some silver zeolite antimicrobial products those for thin or transparent articles are glass-based. 

Polystyrene (PS) Mass produced transparent articles, yoghurt pots, fast food foamed packaging, cassettes Packaging 5 years Cassettes 10 years... 

Processing properties of syndiotactic polypropylene have been improved by blending with isotactic polypropylene. It has allowed a syndiotactic polypropylene-based polymer to process well with conventional processing machines in conventional operating conditions. The transparent articles with moderate rigidity can be... 

The most widely used are acrylics and acrylates, which are close to PVC in refractive index and readily dispersed, so that phase separation and stress whitening in transparent articles are minimised. ABS modifiers are used in a wide variety of rigid PVC articles, including pipe and other extrusions, mouldings and calendered sheet. Chlorinated polyethylene is also used in PVC film, and exhibits good weathering and chemical resistance. 

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