Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
  • B03B—SEPARATING SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS
  • B03B5/00—Washing granular, powdered or lumpy materials; Wet separating
  • B03B5/02—Washing granular, powdered or lumpy materials; Wet separating using shaken, pulsated or stirred beds as the principal means of separation
  • B03B5/10—Washing granular, powdered or lumpy materials; Wet separating using shaken, pulsated or stirred beds as the principal means of separation on jigs
  • B03B5/24—Constructional details of jigs, e.g. pulse control devices
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
  • C08K5/00—Use of organic ingredients
  • C08K5/04—Oxygen-containing compounds
  • C08K5/05—Alcohols; Metal alcoholates

Definitions

• Polycarbonate resins are well known. They may be made, for example, by reacting diphenylcarbonate or phosgene with 2,2'-bis(4-hydroxyd-iphenyl)propane, generally known as bis-phenol A, or by reacting such bisphenol A with its bis-chloro carbonic acid ester. Polycarbonate resins, their preparation and certain solubility characteristics are described in Belgian Patents 562,543, 546,375, 546,376, 546,377, 553,614, 555,894, and 560,610; French Patents 1,152,155 and 1,152,156; German Patents 959,479 and 1,024,710; and U.S. Patent 2,799,666.
• Polycarbonates while possessing certain properties allied to polyethylene terephthalates, are distinguished, in part, by the fact that they may not only be extruded but, because of their solubility in certain solvents, may also be cast.
• the polycarbonates are soluble in such solvents as dioxane, ethylene dichloride, tetrachlorethane, benzene, toluene, chlorobenzene, trichloroethylene, chloroform and the like. It is therefore possible to provide casting dopes for the polycarbonates by dissolving the resin in one or a mixture of the above solvents.
• Polycarbonate resins are cast at a relatively slower speed than cellulose acetate or cellulose acetate butyrate under similar casting and curing conditions.
• the polycarbonate film tends to adhere to the hydrolyzed hydroacetate casting surface and when stripped therefrom causes snap bars at the strip off point.
• Casting dopes of polycarbonate resin so modified and the casting of polycarbonate from such dopes constitute the purposes and objects of the present invention.
• the quantities of the alcohol which are employed are very low compared to the over-all weight of the casting dope, amounting generally from about .02 to 1% by' r. CC
• the casting speed may vary from about 3 /2 to 20 ft. per minute, preferably 7 ft. per minute. Best results are found to accrue at the latter point.
• the alcohol additions to the casting dope not only avoid formation of snap bars but, furthermore, noticeably reduce the stripping tension required.
• the regular polymrbonate film i'.e., without the alcohol addition, required amuch higher stripping tension than the modified polycarbonate.
• the alcohol additions were found to have no eflfgect on the otherwise excellent characteristics of the filmase.
• Example I 20 grams of polycarbonate resin preferably produced by ester-interchange, i.e., reaction of diphenyl carbonate with -bis-phenol A, were dissolved in grams of methylene dichloride. To the resulting casting dope, there was added .125 gram of lauryl alcohol and the dope was cast to produce a film. The film was superior to that resulting from the casting of the resin from the methylene dichloride solution alone, exhibited no snap bars and was stripped at less tension than the resin cast from the methylene dichloride alone.
• ester-interchange i.e., reaction of diphenyl carbonate with -bis-phenol A
• Example II Example I was repeated excepting that the quantity of lauryl alcohol was increased to .25 gram. A noticeable improvement over that of Example I was obtained.
• Example III The procedure was the same as in Example I excepting that the quantityof lauryl alcohol was increased to .35 gram. A still further improvement resulted.
• Example IV The procedure was the same as in Example I except- 7 ing that the quantity of lauryl alcohol was increased respectively to .5 and .75 gram. With these quantities, the results were found to be extremely good.
• Example V The procedure was the same as in Example I excepting that the quantity of lauryl alcohol was increased to 1 gram. Excellent results were obtained but it was found that the film was slightly greasy, indicating that the top limit of alcohol addition had been approximately reached.
• Example VI Four batches of a casting dope were prepared by dissolving for each batch 20 grams'of polycarbonate resin in 80 grams of methylene dichloride.
• Example VII I The dope solution was prepared by dissolving 20 grams of polycarbonate resin in 80 grams of methylene dichloride, to which was added .5 gram of benzyl alcohol.
• the methylene dichloride solvent may be replaced by any other of the usual solvents for polycanbonates, such as dioxane, ethylene dichloride, benzene, toluene or the like.
• a casting dope capable upon stable casting of yielding film strippab-le from the casting surface without the creation of snap bars consisting of polycarbonate resin, an organic solvent therefor and from about .02 to 1% by Weight of the casting dope of an alcohol selected from the class consisting of lauryl alcohol, myristyl alcohol, benzyl alcohol and mixtures of lauryl alcohol and myristyl alcohol.

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• Chemical & Material Sciences (AREA)
• Health & Medical Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Medicinal Chemistry (AREA)
• Polymers & Plastics (AREA)
• Organic Chemistry (AREA)
• Moulding By Coating Moulds (AREA)
• Compositions Of Macromolecular Compounds (AREA)
• Manufacture Of Macromolecular Shaped Articles (AREA)

Priority Applications (4)

Applications Claiming Priority (1)

Publications (1)

Family

ID=22089868

Family Applications (1)

Country Status (3)

Cited By (5)

Families Citing this family (3)

Citations (5)

• 0
  • BE BE610269D patent/BE610269A/xx unknown
• 1960
  • 1960-11-16 US US69569A patent/US3164651A/en not_active Expired - Lifetime
• 1961
  • 1961-11-14 DE DEG33576A patent/DE1174979B/de active Pending

Patent Citations (5)

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