Abstract: The disclosure relates to methods and materials useful for depolymerizing a polymer. In one embodiment, for example, the disclosure provides a method for depolymerizing a polymer containing electrophilic linkages, wherein the method comprises contacting the polymer with a nucleophilic reagent in the presence of a guanidine-containing compound. The methods and materials of the disclosure find utility, for example, in the field of waste reclamation and recycling.

Abstract: The disclosure relates to methods and materials useful for polymerizing a monomer. In one embodiment, for example, the disclosure provides a method for polymerizing a monomer containing a plurality of electrophilic groups, wherein the method comprises contacting the monomer with a nucleophilic reagent in the presence of a guanidine-containing catalyst. The methods and materials of the disclosure find utility, for example, in the field of materials science.

Abstract: The disclosure relates to methods and materials useful for depolymerizing a polymer. In one embodiment, for example, the disclosure provides a method for depolymerizing a polymer containing electrophilic linkages, wherein the method comprises contacting the polymer with a nucleophilic reagent in the presence of a guanidine-containing compound. The methods and materials of the disclosure find utility, for example, in the field of waste reclamation and recycling.

Abstract: Substituted guanidine derivatives of the formula I ##STR1## are prepared by reacting calcium cyanamide with a primary or secondary amino carboxylic acid or a primary or secondary amino sulfonic acid or their derivatives of the formula II ##STR2## where the substituents R.sup.1 and R.sup.2 have the meanings explained in the description.

Abstract: Pyrazol-4-ylbenzoyl compounds of the formula I ##STR1## where Z is a 5- or 6-membered heterocyclic saturated or unsaturated radical, Q is a pyrazole ring and L and M are as defined in the specification, their use as herbicidal compounds and to processes for preparing the compounds.

Abstract: The present invention provides a process for the production of guanidine nitrate by the reaction of urea and excess ammonium nitrate in the presence of a silicon dioxide catalyst at an elevated temperature, wherein the molten reaction mixture containing the dispersed catalyst is passed in a cycle, a branch current of the reaction mixture is continuously separated off by filtration in such a manner that the catalyst remains in circulation and consumed urea and ammonium nitrate are supplemented corresponding to the removal of the product.

Abstract: A process of preparing spherical high bulk density nitroguanidine by dissing low bulk density nitroguanidine in N-methyl pyrrolidone at elevated temperatures and then cooling the solution to lower temperatures as a liquid characterized as a nonsolvent for the nitroguanidine is provided. The process is enhanced by inclusion in the solution of from about 1 ppm up to about 250 ppm of a metal salt such as nickel nitrate, zinc nitrate or chromium nitrate, preferably from about 20 to about 50 ppm.

Abstract: A method of preparing compact nitroguanidine of high bulk density by crystallization from an initially hot nitroguanidine solution. The solution is cooled, while being agitated, at a temperature gradient of at least 3.degree. C./minute, with the crystallization taking place, only at temperatures less than 50.degree. C., from a supersaturated solution. The solvent for the nitroguanidine solution is selected from the group consisting of polyhydric, lower aliphatic alcohols, the mono- or dialkyl ethers of these polyhydric, lower aliphatic alcohols, dimethylformamide, dimethyl sulfoxide, or mixtures thereof. The formed nitroguanidine, in addition to having a high bulk density, has a compact form which makes it possible to prepare a slurry from nitroguanidine and to be able to process nitroguanidine as a composition amenable to casting.

Abstract: In a process for the production of guanidine nitrate from urea and ammonium nitrate, in the presence of SiO.sub.2 catalyst under increased temperature whereby the initial mixture of urea and ammonium nitrate contains an excess of ammonium nitrate which is kept practically constant up to the conversion of the total urea portion during the operation up to the final phase, the catalyst is removed by filtration. It is slurried up several times by means of molten ammonium nitrate or a mixture of ammonium nitrate/urea at 135.degree.-200.degree. C. together with the adherent components like ammonium nitrate, guanidine nitrate and by-products like triazenes. Hereby the components adherent to the catalyst are replaced and removed by subsequent filtration.

Abstract: In a process for the production of guanidine nitrate from a mixture of urea and ammonium nitrate in the presence of a catalyst containing silicium oxide at increased temperature, the initial mixture of urea and ammonium nitrate having an excess of ammonium nitrate, urea is added stepwise to the existing mixture of urea and ammonium nitrate and the catalyst during the procedure in quantities so that the weight ratio of urea: ammonium nitrate is permanently in favor of an excess of ammonium nitrate. The weight ratio is practically maintained during the process and is increased only in the final phase. An apparatus for the performance of the process of the invention comprises a reactor system including one or several substantially horizontal, tubular, heatable reactors in a series. The reaction mass is introduced together with the catalyst in the form of a melt and moved through the reactor system by means of a stirrer and a conveyor.

Abstract: A method of separating acids or bases from vapors which are conveyed along with distillation vapors during concentration of a solution, comprising, passing said distillation vapors containing an acid or base, while being maintained at their existing pressure and temperature, through a salt solution which boils at said temperature and pressure, wherein, if an acid is to be removed from the distillation vapors, the salt solution contains a salt having an anion corresponding to that of the acid while being supplied with a base in an amount required to neutralize the acid, the cation of the base proportion corresponding to that of the salt, while, if a base is to be removed from the distillation vapors, the salt solution contains a salt having a cation corresponding to that of the base while being supplied with an acid in an amount required to neutralize the base in the distillation vapors, the anion of the acid corresponding to that of the salt so that salts are formed during neutralization which correspond to t

Abstract: A continuous process for forming spheroidal high bulk density nitroguanid crystals from an aqueous solution of nitroguanidine which contains methylcellulose and partially hydrolyzed poly(vinyl alcohol) as crystal habit modifiers. A saturated aqueous solution of nitroguanidine is formed at a temperature T.sub.1 where 70.degree. C..ltoreq.T.sub.1 .ltoreq.100.degree. C. and crystallization occurs at a lower temperature T.sub.2 where 20.degree. C..ltoreq.T.sub.1 -T.sub.2 .ltoreq.50.degree. C.