Hoechst Celanese Corporation

Other

Celanese Gmbh

Donna L Keene

Bakulesh N Shah

Dung Q Tran

Darrell D Hicks

Raymond W Rupp

Richard Vicari

Siegbert Rittner

Carl David Murphy

Jack Chosnek

Daniel D Lindley

Volker Hautzel

George E Beck

A method for producing 4-acetoxystyrene by heating 4-acetoxyphenylmethylcarbinol, with an acid catalyst, at a temperature of from about 85.degree. C. to about 300.degree. C. under a pressure of from about 0.1 mm HgA to about 760 mm HgA for from about 0.2 minutes to about 10 minutes. The process also provides for the solventless (neat) hydrogenation of 4-acetoxyacetophenone to produce 4-acetoxyphenylmethylcarbinol. The reaction proceeds by heating at 54.degree. C. to 120.degree. C. with an excess of hydrogen in the presence of a Pd/C or activated nickel such as Raney Nickel catalyst in the absence of a solvent. The 4-acetoxyphenylmethylcarbinol may then be dehydrated to 4-acetoxystyrene. The later may be polymerized to poly(4-acetoxystyrene) and hydrolyzed to poly(4-hydroxystyrene).

Process for the preparation of 4-acetoxyphenylmethyl carbinol

Process for the production of poly(4-acetoxystyrene)

Process for the production of poly(4-hydroxystyrene)

Process for the production of 4-acetoxystyrene, its polymers and

The present invention relates to a process for the purification of 4-acetoxystyrene from a crude product mixture comprising 4-acetoxystyrene and typically 5 or more contaminants in substantial amount. The crude product mixture is purified by melt crystallization by cooling the mixture to a temperature ranging from about +8.degree. C. to about -50.degree. C., whereby at least a first portion of the mixture is crystallized; removing the liquid remaining from contact with the crystallized first portion of the mixture; and, subsequently slowly heating the crystallized first portion, while simultaneously removing liquid which forms due to the heating, whereby impurities contained in the liquid which forms are removed from the crystallized first portion. Surprisingly, despite the large number of contaminants present, and use of the process to purify crude product mixtures containing as little as 50% by weight 4-acetoxystyrene, purities as high as 99.9% by weight have been obtained using multiple melt-crystallization steps of the process of the invention.

Process for the purification of 4-acetoxystyrene

A process for the solventless (neat) hydrogenation of 4-acetoxyacetophenone to produce 4-acetoxyphenyl methylcarbinol. The reaction proceeds by heating at 54.degree. C. to 120.degree. C. with an excess of hydrogen in the presence of a Pd/C or activated nickel such as Raney Nickel catalyst in the absence of a solvent. The 4-acetoxyphenyl methylcarbinol may then be dehydrated to 4-acetoxystyrene. The later may be polymerized to poly(4-acetoxystyrene) and hydrolyzed to poly(4-hydroxystyrene).

Neat (solventless) hydrogenation of 4-acetoxyacetophenone in the

Polymers of 4-acetoxystyrene in finely divided particulate form are suspended in water, and while in suspension are hydrolyzed to polymers of 4-hydroxystyrene using aqueous nitrogen bases. Such polymers are useful in photoresists, as protective coatings for metal, in the manufacture of epoxy resins and epoxy resin curing agents.

Hydrolysis of poly(acetoxystyrene) in aqueous suspension

A coating composition which is a uniformly dispersed admixture of

Poly(epoxide) coatings containing a mannich base of a hydroxystyrene

Protective coatings of a cured hydroxystyrene mannich base and blocked

A surface or electrically active material comprising an alternating copolymer having the formula ##STR1## wherein X and Y oppositely consist of an electron accepting and an electron donating group or a hydrophobic group and an ionic or non-ionic hydrophilic group.

Surface or electrically active copolymers of poly(4-substituted

4-Acetoxystyrene is homopolymerized and copolymerized in aqueous emulsion and, without isolation, the polymer is hydrolyzed to homopolymers and copolymers of p-vinylphenol with a base. Homopolymers and copolymers of p-vinylphenol are used as epoxy resin curing agents and in the preparation of epoxy resins by reaction with epichlorohydrin.

Emulsion polymerization of 4-acetoxystyrene and hydrolysis to

A process is provided for the distillation of a composition containing 4-hydroxyacetophenone and hydrogen fluoride in the presence of an alkane assisting solvent having from 4 to 16 carbon atoms e.g. n-hexane or n-octane. The process is carried out to obtain an overhead vapor containing alkane solvent and most of the hydrogen fluoride in the feed, and a liquid residue containing most of the 4-hydroxyacetophenone in the feed. The overhead vapor is condensed to form two immiscible phases, one containing a preponderance of hydrogen fluoride and the other a preponderance of alkane solvent, with the latter phase being returned to the distillation as reflux. The liquid residue also separates into two immiscible layers, one containing most of the 4-hydroxyacetophenone in the feed which is recovered and the other a preponderance of alkane solvent.

Growing community of inventors

Carrollton, VA, United States of America

Donna L Keene