Preparation of telechelic hydroxyl low molecular weight fluoropolymers by reduction reaction was presented. The telechelic carboxyl low molecular weight fluoropolymers were chosen as raw materials which were prepared by oxidative degradation method. The molecular weights of telechelic carboxyl low molecular weight fluoropolymers were about 3700. Then, using lithium aluminum hydride reacted with carboxyl groups to prepare the telechelic hydroxyl low molecular weight fluoropolymers. The effects of reaction temperatures, reaction times, contents of solvent and lithium aluminum hydride were investigated in detail. The structures, Mn and dynamic viscosity of low molecular weight fluoropolymers were analyzed by FTIR, 1H-NMR, GPC and viscometer respectively. Finally telechelic hydroxyl low molecular weight fluoropolymers were prepared. The conversion rate of that reduction reaction was about 95%. The product was a viscous fluid with a dynamic viscosity of 48Pa·s at 50°C.

In this paper silane coupling agents A151, A171, A174 and A187 were used to modify the surface of nanosilica (SiO 2 ) and polybutadiene (PB)/SiO 2 nanocomposites (NC) had been prepared by in situ anionic polymerization. The morphology and chemical constitution of NC were characterized by Transmission electron microscopy (TEM) and Fourier-transform infrared spectroscopy (FTIR); Thermogravimetric analysis (TGA) was used to investigate the thermal properties of NC; the molecular weight and molecular weight distribution of NC were characterized by gel permeation chromatography (GPC). The effect of different SiO 2 and silane coupling agents on the molecular weight and distribution of PB, microstructure and properties were studied. The results showed that the hydrophobicity of SiO 2 was increased after the surface modification by silane coupling agents and can disperse in PB matrix uniformly. The thermal stability of NC also increased.

The friction and wear properties of the water lubricated rubber bearing, made of the nitrile butadiene rubber (NBR), were studied in this article. The results showed that adding the appropriate amounts of carbon black and molybdenum disulfide (MoS2) could reduce the friction coefficient and the abrasion loss to the minimum values. Meanwhile, the general laws of the two parameters with different loads, rotational speeds and lubricant media have been discovered: the values of friction coefficient and abrasion loss of the rubber bearing, lubricated in both water and seawater, increase firstly and then gradually decrease with the increasing loads.When the loads exceed 500N, the values increase drastically. And the values of friction coefficient and abrasion loss decline with the increasing rotating speed. Moreover, the values of these two parameters in seawater were a little bit higher than those in water. The friction and wear mechanisms of water lubricated rubber bearing were also discussed..

The main-chain structure and chlorine distribution of chlorosulfonated polyethylene (CSM), which was prepared via gas-solid phase method, were studied in this article. All the structure types of CSM 3550 and CSM 3570 were completely characterized by Nuclear Magnetic Resonance (NMR). According to the1H NMR and13C NMR spectra, the chlorine content (Cl wt %) and sulfur content (S wt %) of CSM 3550 and CSM 3570 could be completely calculated and this value was much close to the theoretical values, which were provided by the manufacturer. The comparison shows that the chlorine distribution of CSMs via gas-solid phase method is more uniform than that of CSMs via solution method.