摘要:
Described herein is a process for preparing crystalline polyarylates which comprises (a) forming a crystalline polyarylate prepolymer having a reduced viscosity of from 0.05 to about 0.4 dl/g by reacting at least one diester derivative of a dihydric phenol with at least one aromatic dicarboxylic acid in the presence of a solvent, at a temperature of from about 250.degree. to about 300.degree. C., and (b) heating the prepolymer so formed below its melting point to form a crystalline polyarylate having a reduced viscosity of from about 0.45 to about 1.2 dl/g.
摘要:
Described herein is a process for preparing polyarylates of improved color which comprises reacting a diester derivative of a dihydric phenol with an aromatic dicarboxylic acid in the presence of from about 10 to about 60 weight percent of at least one cycloaliphatic, substituted aromatic or heteroaromatic compound, which compounds contain at least one benzylic and/or tertiary hydrogen atom, at a temperature of from about 260.degree. to about 350.degree. C. Optionally, the process may be carried out in the presence of a magnesium, manganese, or zinc catalyst.
摘要:
Polyarylates derived from a mixture of iso- and terephthalic acids and 4,4'-biphenol and bisphenol A were found to afford melt stable polyesters having good solvent and stress crack resistance.
摘要:
Described herein is a process for preparing polyarylates which comprises reacting a diester derivative of a dihydric phenol with an aromatic dicarboxylic acid in the presence of from about 10 to about 60 weight percent of at least one particular halogenated and/or etherated substituted aromatic or heteroaromatic compound, at a temperature of from about 260.degree. to about 350.degree. C.
摘要:
Curable isocyanate prepolymers have been made in which all or a portion of the available isocyanate terminal groups have been reacted with a secondary amine-containing silane monomer having two trialkoxy silane groups.
摘要:
Disclosed is a process of recycling and reusing an aqueous degreasing solution for further use as a component of a coolant solution which is itself recycled and reused in metal cutting machines. Also disclosed is a method of degreasing parts, and a degreasing apparatus which is controlled such that an appropriate amount of the aqueous degreasing solution is introduced into the coolant solution. Finally, disclosed herein is a method and system for preparing a coolant in which an aqueous degreasing solution is further utilized as a feeder solution for a coolant solution, with the resulting solution being able to be separated into its component parts and reused in the cutting and cleaning of metals to form metal parts.
摘要:
Described herein is a process for preparing polyarylates which comprises reacting a diester derivative of a dihydric phenol with an aromatic dicarboxylic acid in the presence of from about 10 to about 60 weight percent of a diphenyl ether compound at a temperature of from about 260.degree. to about 350.degree. C. and in the presence of a magnesium catalyst.
摘要:
Described herein is a process for preparing polyarylates which comprises reacting a diester derivative of a dihydric phenol with an aromatic dicarboxylic acid in the presence of from about 10 to about 60 weight percent of a diphenyl ether compound at a temperature of from about 260.degree. to about 350.degree. C.
摘要:
Disclosed is a process of recycling and reusing an aqueous degreasing solution for further use as a component of a coolant solution which is itself recycled and reused in metal cutting machines. Also disclosed is a method of degreasing parts, and a degreasing apparatus which is controlled such that an appropriate amount of the aqueous degreasing solution is introduced into the coolant solution. Finally, disclosed herein is a method and system for preparing a coolant in which an aqueous degreasing solution is further utilized as a feeder solution for a coolant solution, with the resulting solution being able to be separated into its component parts and reused in the cutting and cleaning of metals to form metal parts.
摘要:
Disclosed is a process of recycling and reusing an aqueous degreasing solution for further use as a component of a coolant solution which is itself recycled and reused in metal cutting machines. Also disclosed is a method of degreasing parts, and a degreasing apparatus which is controlled such that an appropriate amount of the aqueous degreasing solution is introduced into the coolant solution. Finally, disclosed herein is a method and system for preparing a coolant in which an aqueous degreasing solution is further utilized as a feeder solution for a coolant solution, with the resulting solution being able to be separated into its component parts and reused in the cutting and cleaning of metals to form metal parts.