Reactive blending, thermoplastic

TPEs prepared from rubber-plastic blends usually show poor high-temperature properties. This problem could be solved by using high-melting plastics like polyamides and polyesters. But, often they impart processing problems to the blends. Jha and Bhowmick [49] and Jha et al. [50] have reported the development and properties of novel heat and oil-resistant TPEs from reactive blends of nylon-6 and acrylate rubber (ACM). The properties of various thermoplastic compositions are shown in Table 5.4. In this kind of blend, the plastic phase forms the continuous phase, whereas... 

Jha, A. and Bhowmick, A.K., Thermal degradation and ageing behaviour of novel thermoplastic elastomeric nylon-6/acrylate rubber reactive blends, Polym. Degrad. Stab., 62, 575, 1998. 

Keywords Dynamic vulcanization Polymer blends and alloys Reactive processing Thermoplastic elastomers Thermoplastic vulcanizates... 

Jalali-Arani A, Katbab AA, Nazockdast H (2003) Preparation of thermoplastic elastomers based on silicone rubber and polyethylene by thermomechanical reactive blending Effects of polyethylene structural parameters. J Appl Poly Sci 90(12) 3402-3408... 

Wilkinson, S. P., et al., Reactive Blends of Amorphous Functionalized Engineering Thermoplastics and Bismaleimide/Diallyl Bisphenol A Resins for High Performance Composite Matrices, Polymer Preprints, vol. 33, no. 1, 1992, p. 425. 

The sales of plastics continue to increase in a large part due to technical and economic advancements of polymer blends. Reactive blending is a useful technique for elastomers but, it appears that chemistry could also play an important role in the correct microstructure adjustment of thermoplastic alloys. Interfacial reactivity should be the focal point in maintaining the expected structure during subsequent stages of manufacture. Besides industrial examples, various kinds of polymeric co-reacting systems are also presented in order to emphasise the key factors of reactive blending. 

Fritz HG et al (1994) Tailor-made thermoplastics by reactive blending, PPS Enrop. Regional meeting, Strasbourg, 29-31 Aug 1994... 

Reactive blending of thermoplastic starch/polymer blends has been examined recently and aims to increase properties and performance via control of blend morphologies. Mani [58, 59] examined different techniques for compatibilising starch-polyester blends. They examined development of maleic anhydride grafted polyester/starch blends and starch-g-polycaprolactone... 

Numerous nylon blends prepared by compatibilization or reactive blending are commercially successful. The modifiers fiequenfly utilized in commercial nylon blends include polyolefin, thermoplastic polyolefin, thermoplastic polyunethane, ionomer, elastomer, ethylene-propylene rubber, nitrile mbber, polyftetrafluoroethylene), poly (phenylene ether), poly(ether amide), silicone, glass fiber, and carbon fiber. The nonpolar modifiers such as polyolefin, maleic anhydride or a polar vinyl monomer such as acrylic acid, methaciylic acid and fimiaric acid is fiequently incorporated to introduce reactive sites in nylon. 

As seen from this scheme, functionalized POs play an important role as reactive compatibilizers in the preparation of PO nanocomposites and various PO/thermoplastics (s)mthetic and natural polymers) reactive blends and their hybrid nanocomposites in melt by reactive extrusion in situ processing. Therefore, before discussing the results on PO nanocomposites, it is necessary to describe here some types and methods (predominantly extrusion methods) for the synthesis of reactive polymer compatibilizers by the fimction-alization of POs with MA and its isostructural analogs. 

Ciardelli, R, Coiai, S., Passaglia, E., Pucci, A., and Ruggeri, G. 2008. Reactive blending of polyolefins to nanostructured functional thermoplastic materials. Polymer International R57 805 36. 

A. Maani, B. Blais, M.-C. Heuzey, P.J. Carreau, Rheological and morphological properties of reactively compatibihzed thermoplastic olefin (TPO) blends, Journal of Rheology 56 (3) (2012) 625-647. 

The blends of thermoplastics with LC polymers exhibit inferior properties due to lack of adequate compatibility between the two phases. However, application of common method of compatibiliza-tion, i.e., adding a third component in the form of a copolymer, having monomer unit of the two polymers, the properties of the blend can be enhanced. Thus, blends of Polyethylene (PE) with LCP can be compatibilized by adding PE-g-LC copolymers. The PE-g-LC copolymers can be produced by either of the two methods, i.e. melt polycondensation of LC monomers in the presence of a PE containing free carboxyl group and by reactive blending of the two. The blends can be prepared in an extruder fitted with internal mixer at high temperature ( 250°C). The mixture of PE and LC polymer... 

Non-reactive polyamide (thermoplastic) resins are higher MW (up to 10,000 g/mol) condensation products of dimer fatty acids and diamines. Such resins are important binders for liquid inks. In the synthesis of these resins, both dibasic acid and diamine components are blended at medium temperatures and reacted until the water of reaction can be distilled off. They are solid umber colored products... 

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