摘要:
Hexasubstituted guanidinium chlorides are prepared by a method which affords them in high yield as aqueous solutions, optionally also containing alkali metal chlorides. The solutions may be employed as sources of hexasubstituted guanidinium salts useful as phase transfer catalysts and the reaction of alkali metal salts of dihydroxyaromatic compounds with substituted imides to form polyetherimides or their intermediates.
摘要:
Hexasubstituted guanidinium chlorides are prepared by a method which affords them in high yield as aqueous solutions, optionally also containing alkali metal chlorides. The solutions may be employed as sources of hexasubstituted guanidinium salts useful as phase transfer catalysts for the reaction of alkali metal salts of dihydroxyaromatic compounds with substituted imides to form polyetherimides or their intermediates.
摘要:
Hexasubstituted guanidinium chlorides are prepared by a method which affords them in high yield as aqueous solutions, optionally also containing alkali metal chlorides. The solutions may be employed as sources of hexasubstituted guanidinium salts useful as phase transfer catalysts for the reaction of alkali metal salts of dihydroxyaromatic compounds with substituted imides to form polyetherimides or their intermediates.
摘要:
An adsorption process uses a non-ion-exchangeable adsorbent polymeric resin of a monoethylenically unsaturated monomer such as styrene and a polyvinylidene monomer such as divinylbenzene for the adsorption of organic bases, such amines, amine salts and guanidinium salts, from high ionic strength aqueous solutions. Desorption may be employed for the recovery of said organic bases, and said adsorbent resin may be regenerated.
摘要:
Diaminoalkyl quaternary ammonium salts are prepared by the reaction of alkyl halides with tertiary diamines having C.sub.2-20 primary alkyl radicals attached to nitrogen and an alkyl radical between the two nitrogen atoms in which at least three carbon atoms separate said nitrogen atoms. Said salts are preferably substantially free from corresponding diamines. They are useful as catalysts for interfacial polycarbonate preparation by the reaction of phosgene with at least one dihydroxyaromatic compound. Polycarbonate preparation using such catalysts is economical in phosgene consumption, is accompanied by a rapid conversion of chloroformate groups to desirable species and affords a product with a very low proportion of unreacted dihydroxyaromatic compound.
摘要:
Bis(halophthalimides) such as, 3-bis[N-(4-chlorophthalimido)]benzene are prepared in slurry in an organic liquid such as o-dichlorobenzene or anisole, by a reaction at a temperature of at least 150° C. between at least one diamino compound, preferably an aromatic diamine such as m- or p-phenylenediamine, and at least one halophthalic anhydride such as 4-chlorophthalic anhydride, in the presence of an imidization catalyst such as sodium phenylphosphinate. The solids content of the reaction mixture is at least about 5% and preferably at least about 12% by weight. The product slurry may be employed directly in the preparation of polyetherimides, and similar slurries may be employed to prepare other polyether polymers.
摘要:
Aromatic polyethers are prepared by displacement polymerization reaction in the presence of a water-immiscible solvent with boiling point at atmospheric pressure of greater than 110° C. and a density ratio to water of greater than 1.1:1 at 20-25° C. The polyethers are purified by processes comprising aqueous extraction, or filtration, or a combination thereof.
摘要:
High molecular weight polycarbonates are prepared from hindered bisphenols in a reaction sequence involving conversion of the hindered bisphenol to the corresponding bischloroformate and subsequent treatment with an amine catalyst and aqueous base to effect polymerization by hydrolysis and condensation of the bischloroformate groups. Tertiary aliphatic and cycloaliphatic amine catalysts bearing at least one methyl group are found to be especially effective in promoting this polymerization reaction. Reaction rates and selectivities are shown to be superior to known methods employing tertiary amines lacking methyl groups attached to nitrogen, such as triethylamine. The inclusion of chain stoppers allows the preparation of well defined mixtures of polycarbonate oligomers from hindered bisphenols. Additionally, the methodology may be used to prepare symmetrical diaryl carbonates from hindered phenols.
摘要:
A continuous process for the preparation of monofunctional aromatic chloroformates (MAC) having the structure (I) wherein n is an integer from 1 to 5, and R1 represents hydrogen, a branched or unbranched alkyl group having from 1-15 carbon atoms, an aryl group which may be substituted or unsubstituted, a cycloaliphatic group which may be substituted or unsubstituted, or an arylalkyl group which may be substituted or unsubstituted, the method comprising the steps of a) introducing 1) an aqueous caustic solution; 2) a carbonyl chloride; 3) at least one monofunctional hydroxyaromatic compound; and 4) at least one inert organic solvent into a continuous reaction system; and b) effecting contact between 1), 2), 3) and 4) for a time and at conditions sufficient to produce a MAC of structure (I).
摘要:
The specification describes a continuous process for the preparation of monofunctional aromatic chloroformates (MAC) having the structure (I) wherein n is an integer from 1 to 5, and R1 represents hydrogen, a branched or unbranched alkyl group having from 1–15 carbon atoms, an aryl group which may be substituted or unsubstituted, a cycloaliphatic group which may be substituted or unsubstituted, or an arylalkyl group which may be substituted or unsubstituted.