Polyolefin-based materials

Chodak [257] has reviewed the properties (include mechanical, processing, orientation) of radiation (UV, y, EB) of polyolefin-based materials include PE, PP, and their blends based on... 

The above achievements depend highly on both the recent advances in rational catalyst design with the aid of computational science represented by DFT calculations and the wide range of catalyst design possibilities that are afforded by FI catalysts. These possibilities are derived from the readily varied steric and electronic properties of the phenoxy-imine ligands. It is expected that future research on FI catalysts will provide opportunities to produce additional polyolefin-based materials with unique microstructures and a chance to study catalysis and mechanisms for olefin polymerization. 

A zirconium-based post-metallocene catalyst can produce PP-fo-PE. This has been reported as 13C NMR evidence of the real block nature for a polyolefin based materials [139]. 

Today, polyolefins and polyolefin-based materials are used in many applications. These applications include transportation (automotive, aerospace), packaging, medical, consumer products (toys, appliances, etc.), electronics, cable and wire coating, thermal and acoustic insulation, and building and constmction. Polyolefins can be extruded as filaments (fibers), films (cast and blown), and pipes/profiles. They can be molded into parts of various shapes. They can be foamed with physical and chemical foaming/blowing or/and can be coated onto other materials. 

Applications in the automotive industry require laminate polyolefin-based materials for the achievement of the multifunctional requirements (good... 

Chodak, I. (1995) Properties of crosslinked polyolefin-based materials. Prog. Polymer Sci., 20, 1165-1199. 

The thermoplasticity of material proteins has been utilised to produce materials using thermal or thermomechanical processes under low hydration conditions, as already employed for starch- or polyolefin-based materials [136, 152]. According to the thermoplastic behaviour of synthetic polymers, the Tg of the proteins involves sudden variations in their physical properties (thermal, mechanical, dielectric properties and so on). The molecular response associated with the transition from the glassy to the rubbery state involves an overall increase in the free volume and macromolecule mobility [153,154]. As for synthetic polymers, the Tg of the proteins is affected by the MW, chain rigidity, size and polarity of the lateral groups, presence of intermolecular bonds or crystalline zones, and also by the plasticiser type and concentration [155,156]. 

New developments in polyolefin-based materials have created a family of polypropylene products with a wide range of physical properties, including the ability to be easily recycled. When utilized by automotive and product designers as a part of a design for disassembly strategy, these compatible materials will vield large sub-assemblies that can be reclaimed with a minimum of handling. 

In 2007 Sumitomo Chemical announced plans to expand production of its lithium ion secondary battery separator Pervio in stages (mid-2008 12 million m /year, end 2008 16 million m /year, mid-2009 25 million m /year). The Pervio separator is made by laminating a polyolefin base material and an aramid heat-resistant layer to provide exceptional heat resistance. Sumitomo Chemical was the first company to commercialize a product with this aramid heat-resistant layer technology. 

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