摘要:
A method for preparing 1,3-dihydroxy-4,6-bis�.alpha.-methyl-.alpha.-.alpha.(4'-hydroxyphenyl)ethyl!benzene represented by the following formula (1): ##STR1## comprising the step of initiating a reaction of resorcin with 4-isopropenylphenol in a mixed solvent which comprises a non-polar solvent and a polar solvent in the presence of an acidic catalyst. The method can easily be handled, ensures a high yield, permits the reduction of impurity content and can provide highly pure 1,3-dihydroxy-4,6-bis�.alpha.-methyl-.alpha.-(4'-hydroxyphenyl)ethyl!benzene. The resulting phenolic compound is useful as, for instance, a branching agent for polycarbonates, polyesters or the like; a raw material for radiant ray-sensitive components for use as resist materials; a raw material for epoxy resins; and a hardening agent for epoxy resins.
摘要:
Herein provided are a method for preparing 1,1,2,2-tetrakis(4-hydroxy-3,5-dimethylphenyl)ethane (TKXE) comprising subjecting two molecules of bis(3,5-dimethyl-4-hydroxyphenyl) methane to dehydration-condensation under oxidizing conditions, an epoxy resin prepared by epoxidating TKXE obtained by the method and an epoxy resin composition comprising TKXE obtained by the method as a hardener and an epoxy resin as well as methods for preparing the resin and composition. The method makes it possible to prepare highly pure TKXE in the form of crystals. Moreover, the epoxy resin and the epoxy resin composition can provide hardened products excellent in physical properties such as heat resistance and mechanical strength.
摘要:
Crystals of 6,6'-dihydroxy-3,3,3',3'-tetramethyl -1,1'-spirobiindane (hereinafter referred to as SPI) are obtained by cooling a phenol solution containing 6,6'-dihydroxy-3,3,3',3'-tetramethyl-1,1'-spirobiindane when crystallization is started at a temperature higher than a transition temperature between SPI and an adduct of SPI with phenol. The crystals are washed with an organic solvent or contacted with water and further washed with an organic solvent. When crystallization is started at a temperature less than the transition temperature, adduct crystals of SPI with phenol are obtained from the phenol solution. Phenol is removed from the adduct crystals and the adduct crystals are contacted with water to obtain a hydrate and further the hydrate is washed with an organic solvent.
摘要:
A method for preparing 1,1,2,2-tetrakis(4-hydroxy-3,5-dimethylphenyl)ethane (TKXE) comprising subjecting two molecules of bis(3,5-dimethyl-4-hydroxyphenyl) methane to dehydration-condensation under oxidizing conditions, an epoxy resin prepared by epoxidating TKXE obtained by the method and an epoxy resin composition comprising TKXE obtained by the method as a hardener and an epoxy resin as well as methods for preparing the resin and composition. The method makes it possible to prepare highly pure TKXE in the form of crystals. Moreover, the epoxy resin and the epoxy resin composition can provide hardened products excellent in physical properties such as heat resistance and mechanical strength.
摘要:
Herein disclosed is a method for simultaneously preparing a highly pure bisphenol F and/or a bisphenol F for general use and a novolak phenol resin and/or a high molecular weight novolak phenol resin comprising the steps of:(1) a preparation step comprising reacting phenol with formaldehyde in the presence of an acid catalyst and removing the acid catalyst, water and the unreacted phenol from the resulting reaction product to give a crude bisphenol F;(2) a distillation step comprising distilling a part of the crude bisphenol F to give a highly pure bisphenol F, as a distillate, having a binuclear moiety-content of not less than 95% by weight and a novolak phenol resin, as a still-bottom product, having a binuclear moiety-content of not more than 15% by area;(3) a step for mixing the highly pure bisphenol F with the remaining crude bisphenol F to give a bisphenol F for general use; and(4) a step for polymerizing the novolak phenol resin with formaldehyde in the presence of an acid catalyst to give a high molecular weight novolak phenol resin.
摘要:
A biocompatible polyester which has improved hydrolyzability obtained by bonding saccharide to the structure of a polymer consisting of a glycolic acid unit and/or a lactic acid unit, and a process for Preparing the biocompatible polyester are disclosed.
摘要:
A process for producing high-purity bisphenol A comprises reacting phenol with acetone in the presence of hydrochloric acid as the catalyst to obtain a product mixture, removing the hydrochloric acid from the product mixture, thereby yielding a liquid mixture, adding water to the liquid mixture, evaporating a water-phenol mixture from the liquid mixture under reduced pressure, thereby cooling the liquid mixture and crystallizing out the adduct of bisphenol A with phenol, and finally recovering bisphenol A from the adduct, wherein an improvement comprises treating the water-phenol mixture with a weakly basic ion-exchange resin and recycling and reusing the treated mixture as the water to be added to the liquid mixture. This process does not causes any troubles such as the corrosion of equipment and the decomposition and discoloration of bisphenol A during distillation.
摘要:
An allyletherificated phenol aralkyl resin is obtained through the reaction of a phenol aralkyl resin with an allyl halide in the presence of a base in an organic solvent at room temperature to 100.degree. C. and changed into an allylated phenol aralkyl resin at 160.degree.-250.degree. C. through Claisen rearrangement. The two resins are low in melt viscosity. Epoxy resin compositions containing the allylated phenol aralkyl resin as the curing agent give cured products being excellent in heat and moisture resistances.
摘要:
A degradable non-woven fabric obtained from an web formed of lactic acid-based polymer filaments comprising of one or more lactic acid-based polymers selected from a poly (DL-lactic acid) having more than 80 mol % of L-lactic acid units, poly (DL-lactic acid) having more than 80 mol % of D-lactic acid units, L-lactic acid/hydroxycarboxylic acid copolymer having 70 mol % or more of L-lactic acid units, and D-lactic acid/hydroxycarboxylic acid copolymer having 70 mol % or more of D-lactic acid units, and a preparation process of the degradable non-woven fabric which has good dimensional stability and can be degraded and disappeared under natural environment when abandoned.
摘要:
A phenolic resin can be obtained by a condensation reaction between a specific trifunctional aromatic compound and a phenolic compound. This resin can be reacted with a curing agent such as a hexamine to give cured articles having excellent heat resistance, electrical properties, wear resistance and chemical resistance, and the phenolic resin is also much more excellent in curing reactivity as compared with conventional techniques.