Abstract: Embodiments of the present invention provide a rubber composition in which solution viscosity and cold flow are improved. The rubber composition according to the embodiments of the present invention may include 20 to 90 wt % of a polybutadiene (A) produced by a metallocene catalyst, having: a cis-1,4-structure in microstructure being 65 to 95 mol %, a vinyl-1,2-structure in microstructure being 4 to 30 mol %, and a weight average molecular weight (Mw) being 2×105 to 1×106.The rubber composition further includes 10 to 80 wt % of polybutadiene (B) having: a Mooney viscosity (ML1+4, 100° C.) being 60 or less, a 5 wt % of styrene solution viscosity (St-cp) being 20 to 110; and St-cp/ML1+4 being 1.0 to 2.5. A total content of the polybutadiene (A) and the polybutadiene (B) is 60 to 100 wt %.

Abstract: Disclosed are a polybutadiene having a controlled microstructure, a narrow molecular weight distribution, minimal gel content, and a low APHA color, a modified polybutadiene, producing methods for both, and a rubber-reinforced styrene resin composition using the same. The polybutadiene of the present invention is characterized in that the ratio (Tcp/ML1+4) of a 5% toluene melting viscosity (Tcp) measured at 25° C. and the Mooney viscosity (ML1+4) at 100° C. is 2.0 or higher, the molecular weight distribution (Mw/Mn) is 2.80 or less, the gel content is 0.06 wt % or less, and the APHA color is 20 or less.

Abstract: Disclosed are a polybutadiene having a controlled microstructure, a narrow molecular weight distribution, minimal gel content, and a low APHA color, a modified polybutadiene, producing methods for both, and a rubber-reinforced styrene resin composition using the same. The polybutadiene of the present invention is characterised in that the ratio (Tcp/ML1+4) of a 5% toluene melting viscosity (Tcp) measured at 25° C. and the Mooney viscosity (ML1+4) at 100° C. is 2.0 or higher, the molecular weight distribution (Mw/Mn) is 2.80 or less, the gel content is 0.06 wt % or less, and the APHA color is 20 or less.

Abstract: A two-stage screw compressor has a low-pressure stage screw compressor and a high-pressure stage screw compressor integrally constructed. Compression space is formed by a male rotor and a female rotor, and operation gas is fed for compression to the compression space. A method of supplying lubrication oil prevents degradation of volumetric efficiency caused by return of lubrication oil, coming from a bearing and a shaft sealing device, to the low-pressure stage screw compressor. As a result, refrigeration capacity is improved and the amount of the lubrication oil is reduced.

Abstract: A method of supplying lubrication oil to a two-stage screw compressor is disclosed in which a low-pressure stage screw compressor and a high-pressure stage screw compressor are integrally constructed. A compression space is formed by a male rotor and a female rotor, and operation gas is fed for compression to the compression space. The method prevents degradation of volumetric efficiency caused by return of lubrication oil, coming from a bearing and a shaft sealing device, to the low-pressure stage screw compressor, and as a result, refrigeration capacity is improved and the amount of the lubrication oil is reduced.

Abstract: A two-stage screw compressor has a low-pressure stage screw compressor and a high-pressure stage screw compressor integrally constructed. Compression space is formed by a male rotor and a female rotor, and operation gas is fed for compression to the compression space. A method of supplying lubrication oil prevents degradation of volumetric efficiency caused by return of lubrication oil, coming from a bearing and a shaft sealing device, to the low-pressure stage screw compressor. As a result, refrigeration capacity is improved and the amount of the lubrication oil is reduced.

Abstract: A method of supplying lubrication oil to a two-stage screw compressor is disclosed in which a low-pressure stage screw compressor and a high-pressure stage screw compressor are integrally constructed. A compression space is formed by a male rotor and a female rotor, and operation gas is fed for compression to the compression space. The method prevents degradation of volumetric efficiency caused by return of lubrication oil, coming from a bearing and a shaft sealing device, to the low-pressure stage screw compressor, and as a result, refrigeration capacity is improved and the amount of the lubrication oil is reduced.