In-line Plasma-induced Graft-copolymerization of Pentaerythritol Triacrylate onto Polypropylene

Pentaerythritol triacrylate （PETA） was successfully grafted onto the plasma-treated isotactic polypropylene （iPP） via the in situ melt processing. The X-ray photoelectron spectroscopy （XPS） results showed that the hydroxyl and carbonyl groups, and peroxides could be generated via plasma treatment. The content of free radical in plasma-treated iPP （PiPP） was measured by 2,2-diphenyl-1- picrylhydrazyl （DPPH）. It was found that the resulting peroxides induced the grafting copolymerization of PETA onto iPP, and the grafted PETA promoted the formation of β-crystal in PiPP, which was evidenced by Fourier transform infrared spectroscopy （FTIR）, differential scanning calorimetry （DSC） and wide-angle X-ray diffraction （WAXD） measurements, respectively.

Fabrication of wear-resistant PA6 composites with superior thermal conductivity and mechanical properties via constructing highly oriented hybrid network of SiC-packed BN platelets

Herein,a strong extensional and shearing field was introduced to construct highly oriented hybrid networks of silicon carbide(SiC)-packed boron nitride(BN)platelets to fabricate high-performance wearresistant PA6 composites.Results show that in-plane and through-plane thermal conductivity(TC)of the prepared PA6 composites with a total filler loading of 20 wt.%reached 1.31 and 0.35 W/(m K),352%and 25%higher than those of pure PA6,respectively.It is attributed to the highly oriented hybrid network that facilitates the formation of efficient thermal conductivity pathways.Temperature monitoring results during friction confirm that high TC favors the friction heat dissipation performance.Meanwhile,the yield strength of PA6 composites increased by 39.1%and they still have excellent ductility with an elongation at break of 207.1%.Finally,the wear rate of PA6 composites decreased sharply by 92.5%.This method can be used to manufacture advanced linear bearing and guideway parts,etc。

Trapping the Short-Chain Odd Carbon Number Olefins Using Nickel(Ⅱ)-Catalyzed Tandem Ethylene Oligomerization and Friedel-Crafts Alkylation of Toluene

Nickel(Ⅱ)complexes with pyrazole-based ligands are widely employed in catalysis of ethylene oligomerization and subsequent Friedel-Crafts alkylation of toluene.We have prepared ten new nickel(Ⅱ)dibromide complexes with various substituted bis(azolyl)methanes.They have been characterized using^(1)H NMR,IR,high resolution mass spectrometry and elemental analysis.The structures of three complexes have been unambiguously established using X-ray diffraction.It was found that these complexes in the presence of Et2AlCl or Et_(3)Al_(2)Cl_(3)are active both in ethylene oligomerization and Friedel-Crafts alkylation processes(activity up to 3720 kgoligomer·mol[Ni]^(−1)·h^(−1)).The use of Et_(3)Al_(2)Cl_(3)results in a higher share of alkylated products(up to 60%).Moreover,catalytic systems activated with Et_(3)Al_(2)Cl_(3)produced small amounts of odd carbon number olefins(up to 0.8%).The Friedel-Crafts alkylation was used as a trap for previously undetected short-chain odd carbon number olefins(C_(3)and C_(5)).