Abstract: Polysuccinimide of varying molecular weight has been prepared by heat polymerization of aspartic acid in the presence of a sulfur-containing dehydrating agent employing a variety of reaction mixtures and reaction conditions. Sulfur trioxide and heat decomposable sulfur trioxide precursor dehydrating agents are preferred for this purpose. The presence of an acid scavenger within the reaction mixture is desirable and leads to a relatively higher molecular weight polysuccinimide, while the absence of an acid scavenger results in a relatively lower molecular weight polysuccinimide.

Abstract: Polysuccinimide is prepared by reacting an unsaturated C.sub.2 dicarboxylic acid or anhydride thereof, e.g., maleic acid, fumaric acid, and maleic anhydride, with a particulate ammonium salt that is thermally decomposable to liberate ammonia. The reaction is carried out at a temperature which is above the thermal decomposition temperature of the ammonium salt and for a time period which is sufficient for the acid or anhydride to react with the ammonia liberated from the ammonium salt and for polymerization to occur. The present method avoids the prior art problems of controlling ammonia losses and water removal. The product polysuccinimide can be readily hydrolyzed to polyaspartic acid or a salt thereof, if desired.

Abstract: Aspartic acid precursors such as mono and diammonium maleate, maleamic acid, ammonium maleamate, ammonium malate and mixtures of these and other precursors are copolycondensed thermally with a variety of mono, di and multifunctional monomers containing amino, hydroxyl and carboxyl functional groups. The resulting condensation copolymers and terpolymers contain succinimide units derived from aspartic acid precursors, condensed with other functional group monomers usually though amide and ester linkages. Hydrolysis of the polysuccinimide copolymers and terpolymers with alkali, alkaline earth and ammonium hydroxide produces aspartic acid copolymer and terpolymer salts.

Abstract: A method of making a semipermeable composite membrane comprising a discriminating layer formed insitu by interfacial polymerization is disclosed. The method provides for removal of a water immiscible solvent for a reactant in the interfacial polymerization by physical means not requiring a phase change such as a water knife, air knife, roller, or rubber blade. Composite membranes having good flux, good salt rejection, and low levels of remaining organic solvent are obtained.

Abstract: Compounds are disclosed which comprise parallel, multiring, porphyrin-related compounds, particularly two-ring phthalocyanine compounds, which have a coordinating atom, either a metal or a metalloid, located at their center. The coordinating atoms in adjacent rings are connected by an oxygen bridge along an axial backbone disposed at right angles to the rings, and the coordinating atom and the ring on one end of the axis has a hydrophilic group attached thereto, while the coordinating atom in the ring at the other end of the axis has a hydrophobic group attached to it. Semiconducting films made from such compounds and devices made from such films, especially gas sensors, are also disclosed.

Abstract: A process for preparing a 3- or 4-hydroxybenzocyclobutene comprises reacting a 3- or 4-halogenzocyclobutene reactant with an alkali metal hydroxide by heating in an aqueous alcohol medium at a temperature from about 50.degree. C. to a temperature at which dimerization or oligomerization of a benzocyclobutene reactant or product is a significant side reaction, in the presence of a metal-containing catalyst, for a time sufficient to convert the halobenzocyclobutene reactant to the hydroxybenzocyclobutene product.

Abstract: Compounds are disclosed which comprise parallel, multiring, porphyrin-related compounds, particularly two-ring phthalocyanine compounds, which have a coordinating atom, either a metal or a metalloid, located at their center. The coordinating atoms in adjacent rings are connected by an oxygen bridge along an axial backbone disposed at right angles to the rings, and the coordinating atom and the ring on one end of the axis has a hydrophilic group attached thereto, while the coordinating atom in the ring at the other end of the axis has a hydrophobic group attached to it. Semiconducting films made from such compounds and devices made from such films, especially gas sensors, are also disclosed.