Polyethylene waxes characterization

The oxidized polyethylene (OZPE) waxes have been characterized by infrared (IH) spectroscopy and nuclear magnetic resonance (%-NMR) spectrometry. IR spectroscopy is able to show the formation of various oxygen-containing groups during the oxidation of the PE waxj 3555 cm" hydroperoxide (R-O-O-H) 3380 cm l hydroxyl (R-OH) 1785 cm l peracid (R-CO-O-O-H) ... 

M.E. Sotomayor, I. Krupa, A. Varez, B. Levenfeld, Thermal and mechanical characterization of injection moulded high density polyethylene/paraffin wax blends as phase change materials. Renewable Energy 68, 140-145 (2014)... 

Comparing the WAXS data determined in bulk to the ones characterizing the surface layer of the systems studied, one can find that their relation does depend on supermolecular structure of components. Sequenced elastomer matrix always produces significantly lower than in bulk degree of crystallinity, no matter the structure of plastomer, whereas the same is followed by amorphous elastomer matrix only when branched polyethylene (LDPE2) of lower crystallinity is added. Amorphous EPDM matrix facilitates crystallization of low molecular weight polyethylene of higher crystallinity (LDPEl) on the surface. 

A survey of the modulus as a function of exfoliation efficiency of Cloisite 30B in polyethylene with a varying degree of chlorine content is provided by Kim and White [44]. Polyethylene (2045 LLDPE produced by Dow) was the control. The wt. % chlorine content increased from chlorinated polyethylene (Tyrin random replacement of hydrogen with chlorine on the polymer backbone 36% chlorine, manufactured by DuPont Dow Elastomers), polyvinyl chloride (334 EG 56.7% chlorine, manufactured by OxyVinyl), chlorinated polyvinyl chloride (TempRite, 63.5% chlorine, manufactured by Noveon), to polyvinylidene chloride (Saran, greater than 71.5% chlorine, manufactured by Dow Chemical). The composites were prepared with a Brabender internal mixer at 180°C and 100 r/min. The composites were prepared with 3, 5, and 10 wt.% Cloisite 30B content. The samples for mechanical testing were prepared by compression molding. The composites were characterized by WAXS and TEM. 

Modification of PE by chlorination is a simple technique to change the polarity, to reduce the crystallinity, and to increase the elasticity of the polymer. Partially chlorinated polyolefin waxes were reported to improve stability of asphalt-polymer blends [20, 21], so we elected to prepare and characterize polyethylenes with various degrees of chlorination to improve the polymer Interaction with polar components of asphalt. The extent of chlorination can be used to vary the crystallinity of the polymer additive. The crystalline domains of polyolefins contribute to high temperature reinforcement while their amorphous domains, which exhibit very low glass transition temperatures, contribute additional toughness and ductility at low temperatures to PO/asphalt blends, particularly those prepared from soft asphalts. 

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