Poly chlorinated

Poly(vinyl chloride) and poly(vinyl acetate) Poly(vinyl chloride), 15% glass-fiber-reinforced Chlorinated poly(vinyl chloride) Poly(vinyl butyral), flexible ... 

Heat stabilizers protect polymers from the chemical degrading effects of heat or uv irradiation. These additives include a wide variety of chemical substances, ranging from purely organic chemicals to metallic soaps to complex organometaUic compounds. By far the most common polymer requiring the use of heat stabilizers is poly(vinyl chloride) (PVC). However, copolymers of PVC, chlorinated poly(vinyl chloride) (CPVC), poly(vinyhdene chloride) (PVDC), and chlorinated polyethylene (CPE), also benefit from this technology. Without the use of heat stabilizers, PVC could not be the widely used polymer that it is, with worldwide production of nearly 16 million metric tons in 1991 alone (see Vinyl polymers). 

Carbon Cha.in Backbone Polymers. These polymers may be represented by (4) and considered derivatives of polyethylene, where n is the degree of polymeriza tion and R is (an alkyl group or) a functional group hydrogen (polyethylene), methyl (polypropylene), carboxyl (poly(acryhc acid)), chlorine (poly(vinyl chloride)), phenyl (polystyrene) hydroxyl (poly(vinyl alcohol)), ester (poly(vinyl acetate)), nitrile (polyacrylonitrile), vinyl (polybutadiene), etc. The functional groups and the molecular weight of the polymers, control thek properties which vary in hydrophobicity, solubiUty characteristics, glass-transition temperature, and crystallinity. 

In general, if condensation polymers are prepared with methylated aryl repeat units, free radical halogenatlon can be used to introduce halomethyl active sites and the limitations of electrophilic aromatic substitution can be avoided. The halogenatlon technique recently described by Ford11, involving the use of a mixture of hypohalite and phase transfer catalyst to chlorinate poly(vinyl toluene) can be applied to suitably substituted condensation polymers. 

Chlorinated poly(styrene) samples were prepared by chlorination of PS with CI2 in trifluoroacetic acid(9) or by free radical chlorination using f-butyl hypochlorite(lO) or by chloromethylation using chloromethyl actyl ether and SnCU(ll). 

In the patterning experiments, chlorinated poly(styrene) films were baked at 120 C for 15 mins, in a forced air oven, equilibrated for -12 hrs. inside the humidity-controlled glove box, exposed to deep-UV radiation and treated with TiCU under usual conditions. No significant variation in the lithographic parameters was observed by varying the relative humidity in the 30-60% range in the glove box. 

The residue can be minimized using bilayer schemes and sensitivity can be increased by either using poly(vinyl biphenyl) derivatives that are more absorbing at 248 nm or by adding anthracene derivatives to chlorinated poly(styrene) polymer. The present formulations are not production worthy because of this residue and we are currently working on approaches that may eliminate this problem. 

Figure 11. SEM of 0.4 pm line and space patterns in a 1.2 pm thick chlorinated poly(styrene) film exposed with 250 mJ/cm2 of 248 nm light, treated with TiCl4 and developed by O2 RIE.

Figure 12. Sensitivity curve for 0.8 im thick chlorinated poly(styrene) resist exposed at 248 nm and developed for 21 mins, by O2 RIE.

A photooxidative scheme has been developed to pattern sub half-micron images in single layer resist schemes by photochemical generation of hydrophilic sites in hydrophobic polymers such as poly(styrene) and chlorinated poly(styrene) and by selective functionalization of these hydrophilic sites with TiCU followed by O2 RIE development. Sub half-micron features were resolved in 1-2 pm thick chlorinated poly(styrene) films with exposures at 248 nm on a KrF excimer laser stepper. The polymers are much more sensitive to 193 nm (sensitivity 3-32 mJ/cm2) than to 248 nm radiation (sensitivity -200 mJ/cm2) because of then-intense absorption at 193 nm. 

ISO 580 1990 Injection-moulded unplasticized poly(vinyl chloride) (PVC-U) fittings -Oven test - Test method and basic specifications ISO 727-1 2002 Fittings made from unplasticized poly(vinyl chloride) (PVC-U), chlorinated poly (vinyl chloride) (PVC-C) or acrylonitrile/butadiene/styrene (ABS) with plain sockets for pipes under pressure - Part 1 Metric series ISO 727-2 2002 Fittings made from unplasticized poly(vinyl chloride) (PVC-U), chlorinated poly (vinyl chloride) (PVC-C) or acrylonitrile/butadiene/styrene (ABS) with plain sockets for pipes under pressure - Part 2 Inch-based series ISO 1163-1 1995 Plastics - Unplasticized poly(vinyl chloride) (PVC-U) moulding and extrusion materials - Part 1 Designation system and basis for specifications ISO 1163-2 1995 Plastics - Unplasticized poly(vinyl chloride) (PVC-U) moulding and extrusion materials - Part 2 Preparation of test specimens and determination of properties ISO 1265 1979 Plastics - Polyvinyl chloride resins - Determination of number of impurities and foreign particles... 

ISO 6259-2 1997 Thermoplastics pipes - Determination of tensile properties - Part 2 Pipes made of unplasticized poly(vinyl chloride) (PVC-U), chlorinated poly(vinyl chloride) (PVC-C) and high-impact poly(vinyl chloride) (PVC-HI)... 

ISO 4433-3 1997 Thermoplastics pipes - Resistance to liquid chemicals - Classification -Part 3 Unplasticized poly(vinyl chloride) (PVC-U), high-impact poly(vinyl chloride) (PVC-HI) and chlorinated poly(vinyl chloride) (PVC-C) pipes ISO 6259-2 1997 Thermoplastics pipes - Determination of tensile properties - Part 2 Pipes made of unplasticized poly(vinyl chloride) (PVC-U), chlorinated poly(vinyl chloride) (PVC-C) and high-impact poly(vinyl chloride) (PVC-HI)... 

ISO 7675 2003 Plastics piping systems for soil and waste discharge (low and high temperature) inside buildings - Chlorinated poly(vinyl chloride) (PVC-C)... 

ISO 15877-3 2003 Plastics piping systems for hot and cold water installations - Chlorinated poly(vinyl chloride) (PVC-C) - Part 3 Fittings ISO 15877-5 2003 Plastics piping systems for hot and cold water installations - Chlorinated poly(vinyl chloride) (PVC-C) - Part 5 Fitness for purpose of the system ISO/TS 15877-7 2003 Plastics piping systems for hot and cold water installations -Chlorinated poly(vinyl chloride) (PVC-C) - Part 7 Guidance for the assessment of conformity... 

Figure 4 Electron micrographs of unchlorinated poly(vinyl acetate-co-oxazolidinone) (top) and chlorinated poly(vinyl acetate-co-oxazolidinone) (bottom) coated medical catheters exposed for 72 h to a flowing aqueous suspension of Pseudomonas aeruginosa (10 CFU/mL). 

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