摘要:
The present invention provides spherical rubber chemicals and the method for preparing the same. The spherical rubber chemicals of the present invention include spherical antioxidants, spherical vulcanization agents, spherical processing aids, spherical reinforcing agents, or spherical adhesive agents. With the spherical rubber chemicals of the present invention, the shortcomings of powdery or semi-spherical rubber chemicals are overcome, including eliminating the dust pollution during granulation procedure and avoiding the raw material loss and the environmental pollution, while solving the quality problem of lower melting point of product caused by the presence of fine powder crystal. Furthermore, the resultant rubber chemicals has an improved smoothness of surface, which is helpful to improve the flowing and mixing behaviors of the rubber chemicals in mixing or open milling process with rubbers.
摘要:
The present invention discloses a method for producing 4-aminodiphenylamine by reacting nitrobenzene with a aniline in the presence of complex base catalyst for condensation and complex powdery catalyst for hydrogenation, which comprises the steps of condensation, separation, hydrogenation, separation II and refining sequentially. The method of the present invention can be carried out continuously. By using the complex base catalyst for the condensation, followed being separated and recycling before the hydrogenation, the problem of heat-sensitive decomposition of the complex base catalyst during the hydrogenation procedure can be avoided. Accordingly, the choice of the hydrogenation catalyst is increased, and lower-cost hydrogenation catalysts can be used. Meanwhile, the apparatus can be selected easily and the industrialization can be achieved simply. The complex base catalyst according to the invention is cheaper. The catalystic activity of the catalyst is high and the condition of the reaction is gentle. Additionally, the complex base catalyst is suitable to a wide range of water content. Accordingly the amount of the by-product is decreased, and the conversion and the selectivity can be increased. The labour intensity of the process control is low. Moreover, corrodible liquid is not generated and the environmental pollution can be reduced. The content of 4aminodiphenylamine reaches 99% (by weigh), and yield of the industrial- scale production is greater than 95%.