The wax gel grease (S0) was prepared from a mixture of 2.3:1 base oil blend (base oil grade 260/290, transformer oil), and microcrystalline wax in the presence of 0.1% - 2% of polyoxyethylene sorption nano-palmitate a...The wax gel grease (S0) was prepared from a mixture of 2.3:1 base oil blend (base oil grade 260/290, transformer oil), and microcrystalline wax in the presence of 0.1% - 2% of polyoxyethylene sorption nano-palmitate as antioxidant and 2,2 methylene bis (4-methyle-6-tertiary butyl phenol) as anticorrosion. It was found that the prepared Wax gel grease has inconvenient physico-chemical and dielectric properties, so in order to improve its physico-chemical properties (viscosity, penetration, dropping point and water resistance) and dielectric Properties (dielectric constant, dielectric loss and volume resistivity), Butyl rubber, isoprene rubber and bitumen were added separately as thickening agents to the prepared wax gel in certain proportion at certain frequency range 1 - 1000 KHz at 35°C. The best dielectric properties were achieved by adding butyl rubber to the prepared wax gel.展开更多
Along with the developing technology in the rubber industry, the use of natural and synthetic rubbers as well as liquid rubbers has increased significantly in recent years. The formulation of the tread compound, which...Along with the developing technology in the rubber industry, the use of natural and synthetic rubbers as well as liquid rubbers has increased significantly in recent years. The formulation of the tread compound, which directly affects the performance of a tire, is generally produced from natural and synthetic rubbers. Intensive scientific studies have been carried out on liquid rubbers because they reduce the consumption of process oils used in the tire production phase and increase dispersion. In this study, the rheological and physico-mechanical properties of rubbers developed using only liquid rubber (liquid isoprene and liquid SBR) with four different viscosities and without using process oil (Styrene Butadiene Rubber—SBR) were investigated. It has been observed that the rubber blends produced by adding four different liquid rubbers to the same recipe caused changes in rheological and physico-mechanical properties compared to the reference sample. It was observed that the minimum torque/viscosity (ML), maximum torque/viscosity (MH) and curing time (t90) in some of the formulas tested decreased significantly due to the use of liquid rubber.展开更多
A new approach was developed to prepare high-performance isobutylene-isoprene rubber/swollen organoclay nanocomposites by shear mixing.Compared with traditional melt compounding method,better dispersion of nanoclay la...A new approach was developed to prepare high-performance isobutylene-isoprene rubber/swollen organoclay nanocomposites by shear mixing.Compared with traditional melt compounding method,better dispersion of nanoclay layers in rubber matrix was verified through transmission electron microscopy(TEM) and X-ray diffraction(XRD).The nanocomposites also exhibit significantly improved mechanical properties and gas barrier property.As a mechanism,the molecules of organic swelling agent play a vital role in accelerating the diffusion and intercalation of the matrix molecules.展开更多
A novel rotating packed bed(RPB)technology was used to prepare butyl rubber for the first time.The effects of the operating parameters,such as rotate speed,polymerization temperature,on the molecular weight and molecu...A novel rotating packed bed(RPB)technology was used to prepare butyl rubber for the first time.The effects of the operating parameters,such as rotate speed,polymerization temperature,on the molecular weight and molecular weight distribution of isobutylene-isoprene rubber(IIR)were investigated in the experiment.The results revealed that IIR prepared by the unique high gravity reaction technology with the molecular weight of 2.89×105,molecular weight distribution index of 1.99 and single-pass conversion 30% was obtained at N=1200 r·min-1,Tp=-100℃ in the experimental condition.In addition,the mean residence time of the products was less than 1s while that of the conventional technology was 30—60 min.The production efficiency per unit volume of the equipment was increased by 2—3 orders of magnitude.With increasing N and decreasing Tp,the molecular weight of IIR increased whereas no obvious difference of the distribution index of molecular weight was observed.展开更多
文摘The wax gel grease (S0) was prepared from a mixture of 2.3:1 base oil blend (base oil grade 260/290, transformer oil), and microcrystalline wax in the presence of 0.1% - 2% of polyoxyethylene sorption nano-palmitate as antioxidant and 2,2 methylene bis (4-methyle-6-tertiary butyl phenol) as anticorrosion. It was found that the prepared Wax gel grease has inconvenient physico-chemical and dielectric properties, so in order to improve its physico-chemical properties (viscosity, penetration, dropping point and water resistance) and dielectric Properties (dielectric constant, dielectric loss and volume resistivity), Butyl rubber, isoprene rubber and bitumen were added separately as thickening agents to the prepared wax gel in certain proportion at certain frequency range 1 - 1000 KHz at 35°C. The best dielectric properties were achieved by adding butyl rubber to the prepared wax gel.
文摘Along with the developing technology in the rubber industry, the use of natural and synthetic rubbers as well as liquid rubbers has increased significantly in recent years. The formulation of the tread compound, which directly affects the performance of a tire, is generally produced from natural and synthetic rubbers. Intensive scientific studies have been carried out on liquid rubbers because they reduce the consumption of process oils used in the tire production phase and increase dispersion. In this study, the rheological and physico-mechanical properties of rubbers developed using only liquid rubber (liquid isoprene and liquid SBR) with four different viscosities and without using process oil (Styrene Butadiene Rubber—SBR) were investigated. It has been observed that the rubber blends produced by adding four different liquid rubbers to the same recipe caused changes in rheological and physico-mechanical properties compared to the reference sample. It was observed that the minimum torque/viscosity (ML), maximum torque/viscosity (MH) and curing time (t90) in some of the formulas tested decreased significantly due to the use of liquid rubber.
基金supported by the National Natural Science Foundation of China-Distinguished Youth Foundation (No.50725310)the National Natural Science Foundation of China(No.50873095)+1 种基金the Natural Science Foundation of Shanxi Province of China(No.2009011031)Program for New Century Excellent Talents in Universities(NCET-09- 0873)
文摘A new approach was developed to prepare high-performance isobutylene-isoprene rubber/swollen organoclay nanocomposites by shear mixing.Compared with traditional melt compounding method,better dispersion of nanoclay layers in rubber matrix was verified through transmission electron microscopy(TEM) and X-ray diffraction(XRD).The nanocomposites also exhibit significantly improved mechanical properties and gas barrier property.As a mechanism,the molecules of organic swelling agent play a vital role in accelerating the diffusion and intercalation of the matrix molecules.
文摘A novel rotating packed bed(RPB)technology was used to prepare butyl rubber for the first time.The effects of the operating parameters,such as rotate speed,polymerization temperature,on the molecular weight and molecular weight distribution of isobutylene-isoprene rubber(IIR)were investigated in the experiment.The results revealed that IIR prepared by the unique high gravity reaction technology with the molecular weight of 2.89×105,molecular weight distribution index of 1.99 and single-pass conversion 30% was obtained at N=1200 r·min-1,Tp=-100℃ in the experimental condition.In addition,the mean residence time of the products was less than 1s while that of the conventional technology was 30—60 min.The production efficiency per unit volume of the equipment was increased by 2—3 orders of magnitude.With increasing N and decreasing Tp,the molecular weight of IIR increased whereas no obvious difference of the distribution index of molecular weight was observed.