| Patent Number |
Title Of Patent |
Date Issued |
| 5412060 |
Process for the production of polycarbonate of constant viscosity |
May 2, 1995 |
| The invention relates to a process for the production of polycarbonates by the two-phase interfacial method in which deviations between measured and estimated variables are continuously minimized by means of a suitably selected observer or filter system on the basis of a process model wi |
| 5368699 |
Method of controlling the concentrations of a multicomponent mixture |
November 29, 1994 |
| A method of controlling concentrations in process technology operations--preferentially in thermal separation technology--using a non-linear, pressure-compensated temperature as control signal. The method can be used flexibly within a wide operating range. |
| 5363905 |
Method of controlling heat exchangers using enthalpy flow as the correcting variable |
November 15, 1994 |
| A method of controlling a heat exchanger wherein the enthalpy flow into the heat exchanger serves as a correcting variable. The robust and versatile control method is particularly suitable for use in endothermic reactions and for distillation. |
| 5275758 |
Production of ultrafine suspensions of bisphenol, sodium hydroxide and water |
January 4, 1994 |
| The invention relates to ultrafine suspensions of bisphenol, sodium hydroxide and water for the production of polycarbonates by the two-phase interfacial process. According to the invention, these suspensions are prepared by cooling bisphenolate concentrations near the solubility limit |
| 5260418 |
Washing of polycarbonates with cascading train of centrifuges |
November 9, 1993 |
| A continuous process for the removal of electrolytes and catalysts from organic polycarbonate solutions is disclosed. Accordingly, a solution obtained in the course of the two-phase interfacial reaction for the preparation of polycarbonate, containing thermoplastic aromatic polycarbo |
| 5258484 |
Process for the production of polycarbonate |
November 2, 1993 |
| A process for the continuous production of a thermoplastic aromatic polycarbonate is disclosed. Accordingly, in a reactor system which includes a tube reactor and a tank equipped with a stirrer, there are reacted a preheated dialkali diphenolate aqueous solution with gaseous phosgene |
| 5250658 |
Isolation of polycarbonate with carbon dioxide |
October 5, 1993 |
| According to the invention, a special process for isolating polycarbonate from methylene chloride at temperatures of 30.degree. to 80.degree. C. in the form of a powder with residual solvent contents below 5% by weight is started up as a continuous process by starting up in a two-compone |
| 5248763 |
Isolation of poly(ester)carbonates from methylene chloride using carbon dioxide fluid |
September 28, 1993 |
| A process for isolating a poly(ester)carbonate resin from its methylene chloride solution is disclosed. The process entails combining a solution which contains 5 to 30% by weight resin with carbon dioxide fluid in a two-component nozzle under pressures of 90 to 180 bar and at temperature |
| 5244544 |
Process for the separation of multicomponent systems containing intermediate boiling substances |
September 14, 1993 |
| A process for the separation of multicomponent systems containing intermediate boiling substances in separating separating columns with side discharge, the temperatures T.sub.u and T.sub.o above and below the side discharge are measured on the column or inside the column and the temp |
| 5235026 |
Continuous production of polycarbonates |
August 10, 1993 |
| An improvement to the continuous process for the production of polycarbonates by interphase polycondensation is described. Accordingly, the organic phase and the aqueous phase are combined in a tube, forming chlorocarbonic acid ester and further alkali hydroxide is added at, or short |
| 5229486 |
Process for isolating polymers from their solvents using liquids containing carbon dioxide |
July 20, 1993 |
| A process for isolating polymers from their solvents by addition of fluids containing carbon dioxide at temperatures of 30.degree. to 280.degree. C. and under pressures of 1 to 1,000 bar is disclosed. The process is characterized in that the concentration of the polymers in their solvent |
| 5227458 |
Polycarbonate from dihydroxydiphenyl cycloalkane |
July 13, 1993 |
| Dihydroxydiphenyl cycloalkanes corresponding to the formula ##STR1## in which R.sup.1 and R.sup.2 independently of one another represent hydrogen, halogen, C.sub.1 -C.sub.8 alkyl, C.sub.5 -C.sub.6 cycloalkyl, C.sub.6 -C.sub.10 aryl and C.sub.7 -C.sub.12 aralkyl,m is an integer of fro |
| 5221731 |
Process for isolating polycarbonates with CO.sub.2 under pressure |
June 22, 1993 |
| A continuous process for the isolation of polycarbonates from a solution of polycarbonate in methylene chloride at temperatures of 30.degree. to 80.degree. C. is disclosed. The process which yields polycarbonate in powder form having residual solvent content of less than 5% by weight, is |
| 5198525 |
Aromatic copolyether sulfones |
March 30, 1993 |
| Aromatic polyether sulfones based on 5 to 90 mol-%, based on total bisphenols, of special dihydroxydiphenyl cycloalkanes and 10 to 95 mol-% based on the bisphenols of specific phthaleins, a process for their production and their use as molding compounds. |
| 5149761 |
Aromatic ether imides |
September 22, 1992 |
| The new aromatic ether imides corresponding to the following formula ##STR1## may be used for the production of plastics which in turn may be worked up into moulded articles, films, sheet products and filaments. The plastics produced from the new aromatic ether imides are distinguish |
| 5138031 |
Linear and branched poly-p-arylene sulfide substantially free from defect structures having plur |
August 11, 1992 |
| The invention relates to linear and branched poly-p-arylene sulfides (PAS), preferably poly-p-phenylene sulfides (PPS), which have an extremely low proportion of defect or foreign structures, to a process for their production and to their use for the production of molded articles. |
| 5132154 |
Polycarbonate mixtures in optical applications |
July 21, 1992 |
| An article for an optical application is disclosed comprisinga) about 0.1 to 99.9 wt. % of a thermoplastic, aromatic polycarbonate resin containing carbonate structural units corresponding to (Ia): ##STR1## wherein R.sup.1 and R.sup.2 independently represent hydrogen, halogen, C.sub |
| 5126428 |
Polycarbonate from dihydroxy diphenyl cycloalkane |
June 30, 1992 |
| Dihydroxydiphenyl cycloalkanes corresponding to the formula ##STR1## in which R.sup.1 and R.sup.2 independently of one another represent hydrogen, halogen, C.sub.1 -C.sub.8 alkyl, C.sub.5 -C.sub.6 cycloalkyl, C.sub.6 -C.sub.10 aryl and C.sub.7 -C.sub.12 aralkyl,m is an integer of fro |
| 5115076 |
Aromatic copolyether ketones of dihydroxydiphenyl alkanes and phthaleins and a process for their |
May 19, 1992 |
| Aromatic polyether ketones based on 5 to 90 mol-%, based on the total quantity of all bisphenols, of special dihydroxydiphenyl cycloalkanes and 10 to 95% phthaleins, a process for their production and their use as molding compounds. |
| 5109076 |
Polydiorganosiloxane/polycarbonate block cocondensates based on certain dihydroxydiphenylcycloal |
April 28, 1992 |
| Thermoplastic polydiorganosiloxane/polycarbonate block copolymers based on dihydroxydiphenylcycloalkanes corresponding to the following general formula (I): ##STR1## wherein R.sup.1 and R.sup.2 independently represent hydrogen, halogen, preferably chlorine or bromine, C.sub.1 -C. |
| 5105004 |
Aromatic ethers |
April 14, 1992 |
| The new aromatic ethers of the formulae ##STR1## can be used for the preparation of plastics which, in turn, can be processed further to give moulded articles, films, foils and filaments. The plastics prepared from the new aromatic ethers are distinguished by exceptional dimensio |
| 5104723 |
Mixtures of special new polycarbonates with other thermoplastics or with elastomers |
April 14, 1992 |
| Mixtures containinga) thermoplastic polycarbonates based on diphenols corresponding to formula (I) ##STR1## in which R.sup.1 and R.sup.2 independently of one another represent hydrogen, halogen, C.sub.1 -C.sub.8 alkyl, C.sub.5 -C.sub.6 cycloalkyl, C.sub.6 -C.sub.10 aryl and c.sub |
| 5086157 |
Aromatic polyether sulphones based on dihydroxy-diphenyl-cyclo-alkanes and films therefrom |
February 4, 1992 |
| Polyether sulphones based on diphenols corresponding to the following general formula (I): ##STR1## wherein R.sup.1 and R.sup.2, independently represent hydrogen, halogen, C.sub.1 -C.sub.8 alkyl, C.sub.5 or C.sub.6 cycloalkyl, C.sub.6 -C.sub.10 aryl, or C.sub.7 -C.sub.12 aralkyl; |
| 5010147 |
High-strength polycarbonate mixtures |
April 23, 1991 |
| Mixtures containing(a) 5 to 70% by weight polycarbonate based on 2-(4-hydroxphenyl)-2-(3-hydroxphenyl)-propane and(b) 95 to 30% by weight polycarbonate based on bis-2,2-(4-hydroxy-3,5-dimethylphenyl)propane, the sum of the percentages by weight of components (a)+(b) being 100% by weight. |
| 4994579 |
Aromatic ether imides |
February 19, 1991 |
| The new aromatic ether imides corresponding to the following formula ##STR1## may be used for the production of plastics which in turn may be worked up into moulded articles, films, sheet products and filaments. The plastics produced from the new aromatic ether imides are distinguish |
| 4982014 |
Dihydroxydiphenyl cycloalkanes, their production and their use for the production of high molecu |
January 1, 1991 |
| Dihydroxydiphenyl cycloalkanes corresponding to the formula ##STR1## in which R.sup.1 and R.sup.2 independently of one another represent hydrogen, halogen, C.sub.1 -C.sub.8 alkyl, C.sub.5 -C.sub.6 cycloalkyl, C.sub.6 -C.sub.10 aryl and C.sub.7 -C.sub.12 aralkyl,m is an integer of fro |
| 4964890 |
Aromatic polyether ketones |
October 23, 1990 |
| Polyether ketones based on diphenols corresponding to the following general formula (I): ##STR1## wherein R.sup.1 and R.sup.2, independently represent hydrogen, halogen, C.sub.1 -C.sub.8 alkyl, C.sub.5 or C.sub.6 cycloalkyl, C.sub.6 -C.sub.10 aryl or C.sub.7 -C.sub.12 aralkyl;m r |
