Yi Hongling

Nanoscale-confined crystallization in epoxy resin and polyethylene-block-poly(ethylene oxide) diblock copolymer blends

In this paper, the nanoscale-confined crystallization behavior and crystallization kinetics in blends of double-crystalline polyethylene-block-poly(ethylene oxide) (PE-b-PEO) diblock copolymer with diglycidyl ether of bisphenol A epoxy resin were investigated. The results showed that there appeared three crystallization regimes related to the crystallization of the PE block within three different microenvironments in the epoxy resin/PE-b-PEO blends. The Avrami index n is around 1.8–2.4, suggesting PE block of the copolymer in the blends exhibited nanoscale-confined crystallization behavior by homogeneous nucleation. The PE block nanoscale-confined crystallization is ascribed to the formation of the strong intermolecular hydrogen bonding interaction between hydroxyl groups of amine-cured epoxy and ether oxygen atoms of PEO, as seen from Fourier transform infrared spectroscopy spectra.

Regulation of Nano Silica on Mechanical Properties of Gymnastic Artificial Turf

A new type of LLDPE/nano silica (SiO2) composite based artificial turf fibers with excellent tensile property and abrasion resistance is introduced in this paper. The effect of SiO2 loading on properties shows that the tensile force and elongation at break reached the maximum value when the SiO2 content is 6%, and the abrasion loss of monofilament fibers get to the lowest point. Turf wear test indicates that after 12000 cycles test, the surface morphology of artificial turf weaved from monofilament fibers showed serious abrasion and branching phenomenon of neat LLDPE, while only slight abrasion and branching phenomenon occurred for the artificial turf filled with 6% nano SiO2. SEM images of cross sections of monofilament fibers show that nano SiO2 had a good dispersibility in monofilament fiber matrix.

Study of High-Performance Chloroprene Sponge in Diving Suit Application

A diving-suit-used foam neoprene with high performance has been developed and its aging behaviors in QUV accelerated aging tank and temperature cyclic chamber were investigated. The results show that the tensile strength and tear strength of the material are decreased after 9d QUV accelerated aging due to the obvious cracks in the foaming cell. In temperature cycling the mechanical properties increased arising from cross linking reaction in the aging process. Besides, the chloride ion penetration resistance of the material was tested by dielectric flux intelligent tester, and the result shows that the material is of excellent chloride ion penetration resistance capability. The infiltration coefficient is 8.1×10-11cm2/s.