Nitrile rubber PVC blends

Nitrile rubber/PVC blends have reached a mature stage in their commercial usage. They face increasing competition from other thermoplastic elastomers such as the dynamically vulcanized blends of PP/EPDM and PP/NBR (Santoprene and Geolast , Monsanto-Advanced Elastomer Systems). 

Table 19.16 Typical properties of nitrile rubber/PVC blends vs. nitrile rubber ...

An examination is made of the properties of nitrile rubber/ PVC blends prepared from latex by two different methods. 2 refs. 

Kwak S-Y and Nakajima N (1995) Magic-angle cross-polymerization NMR relaxation analysis of sohd microstructures and their scales in a thermoplastic elastomer prepared from nitrile rubber/PVC blending, Ann Tech Conf Soc Plast Eng 53 3208-3215. 

The complexity that can be present in the TGA thermogram of an extensively compoimded sample is given in Table 6.7 using the example of a flame retardant rubber based on a nitrile rubber/PVC blend [15]. 

Polyblend n. A colloquial term - shortened from polymer blend - used for physical mixtures of two or more polymers, for example, polystyrene and rubber or PVC and nitrile rubber. Such blends usually yield products with favorable properties of both components, sometimes opening markets not available to either of the neat resins. The term alloy is sometimes used for blends. 

PVC/nitrile rubber/DOP blends Halogenated polyolefin/ethylene interpolymer blends... 

Nitrile mbber finds broad application in industry because of its excellent resistance to oil and chemicals, its good flexibility at low temperatures, high abrasion and heat resistance (up to 120°C), and good mechanical properties. Nitrile mbber consists of butadiene—acrylonitrile copolymers with an acrylonitrile content ranging from 15 to 45% (see Elastomers, SYNTHETIC, NITRILE RUBBER). In addition to the traditional applications of nitrile mbber for hoses, gaskets, seals, and oil well equipment, new applications have emerged with the development of nitrile mbber blends with poly(vinyl chloride) (PVC). These blends combine the chemical resistance and low temperature flexibility characteristics of nitrile mbber with the stability and ozone resistance of PVC. This has greatly expanded the use of nitrile mbber in outdoor applications for hoses, belts, and cable jackets, where ozone resistance is necessary. 

Nitrile rubbers are sometimes used in conjunction with plastics. Blends with PVC provide an early example of polyblends. (In fact this word has been used by one company as a trade description for such blends for over 25 years.)... 

The ductility of GRT-polyethylene blends drastically decreases at ground rubber concentration in excess of 5%. The inclusion of hnely ground nitrile rubber from waste printing rollers into polyvinyl chloride (PVC) caused an increase in the impact properties of the thermoplastic matrix [76]. Addition of rubber powder that is physically modihed by ultrasonic treatment leads to PP-waste ethylene-propylene-diene monomer (EPDM) powder blends with improved morphology and mechanical properties [77]. 

Polymers Nitrile rubber 55 PVC 45 blend, 39 % total polymer content... 

PVC decomposition products as health hazard, 25 677 PVC fusion/gelation, 25 663-664 PVC-nitrile rubber blends, 24 717. See also Poly(vinyl chloride) (PVC)... 

Apex N PVC blend with nitrile rubber Teknor Apex... 

S—EB—S (compounds) polyurethane/elastomer block copolymers polyester/elastomer block copolymers polyamide/elastomer block copolymers polyetherimide/polysiloxane block copolymers polypropylene/EPDM or EPR blends polypropylene/EPDM dynamic vulcanizates polypropylene/butyl rubber dynamic vulcanizates polypropylene/natural rubber dynamic vulcanizates polypropylene/nitrile rubber dynamic vulcanizates PVC/ nitrile rubber blends... 

Nitrile rubbers (NBR) are blended into PVC-P formulations giving vinyl based thermoplastic... 

Several investigators have looked at PVC blends with nitrile-butadiene rubber (6, 8), and, although compatibility increased with acrylonitrile content (up to about 40 wt %), micro-heterogeneity was still evident in electron photomicrographs. 

Goodyear markets blends of nitrile rubber with PVC, chlorinated PE, TPU or PA, or then-combination, under the trade name Chemigum TPE. The blends show either a disperse or co-continuous morphology. Properties include excellent oil and fuel resistance, high wear resistance and strength, a brittleness temperature below -45°C and a service temperature up to 120°C. Applications include gaskets, seals, joints, geomembranes, seals and liners. 

Blends of nitrile rubber with PVC or chlorinated PE, TPU, PA or their combination Chemigum TPE) show extremely high resistance to melt fracture and die swell. The material can be fed at high melt temperature into crosshead to promote strong melt-fusion with rigid plastics such as PVC/ABS blends during coextmsion. 

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