Unsaturated polyesters combined with organoaluminum compounds

A process for making a liquid copolymerizable polyester resin comprising the steps of:

• A. condensing at least one polyol with a polycarboxylated material at least one component of which is unsaturated at elevated temperatures to form an unsaturated polyester resin comprised substantially completely of non volatile resin having a molecular weight ranging from about 1,000 to 30,000
• B. dissolving said unsaturated polyester resin in a solvent comprised of at least one vinyl monomer having a molecular weight ranging from about 100 to 250 and having a boiling point greater than about 100.degree. C. to form a first solution comprising initially from about 20 to 90 weight percent of said unsaturated polyester resin with the balance up to 100 weight percent thereof being said vinyl monomer,
• C. admixing said first solution with a second solution comprising initially from about 0.2 to 50 weight percent of at least one organoaluminum compound with the balance up to 100 weight percent thereof being said vinyl monomer to form a product solution comprising on a 100 weight percent total product solution basis:
• 1. from about 20 to 90 weight percent of said unsaturated polyester resin,
• 2. from about 0.1 to 20.0 weight percent of said organoaluminum compound, the exact amount of said organoaluminum compound present in any given such solution being such that such product solution remains in a liquid condition, and
• 3. from about 10 to 80 weight percent of said vinyl monomer solvent,
• said organoaluminum compound being characterized by:
• a. containing at least one aluminum atom per molecule,
• b. containing at least one oxygen atom per molecule,
• c. containing at least four carbon atoms per molecule at least two of which are bonded directly to one another by one or two bonds in a carbon-to-carbon chain,
• d. each said aluminum atom having three bonds and being bonded by at least one of such bonds to one of the carbon atoms in said chain through one of said oxygen atoms intermediately, said carbon atom so bonded having additionally no oxygen atoms double bonded thereto,
• e. being soluble in styrene to a weight percentage at least about equal to the weight percentage of such organoaluminum compound is employed in a given such resin composition,
• f. having a formula weight of from about 130 to 1000, and
• g. causing a cloudy dispersion of alumina particles to form when a 10 weight percent solution of such organoaluminum compound in anhydrous benzene is admixed with benzene saturated with distilled water and the resulting mixture is heated for four hours at 60.degree. C.

A process for increasing and regulating the viscosity of a first solution comprising initially on a 100 weight percent basis

• from about 20 to 90 weight percent of an unsaturated polyester resin having a molecular weight ranging from about 1000 to 30000 and comprised of a condensate of at least one polyol with at least one polycarboxylated compound and
• the balance up to 100 weight percent of any given such first solution being a liquid comprising at least one vinyl monomer having a molecular weight ranging from about 100 to 250 and having a boiling point greater than about 100.degree. C.
• comprising the steps of admixing with said first solution a second solution comprising initially on a 100 weight percent basis
• from about 0.2 to 20.0 weight percent of at least one organoaluminum compound characterized by:
• a. containing at least one aluminum atom per molecule,
• b. containing at least one oxygen atom per molecule,
• c. containing at least four carbon atoms per molecule at least two of which are bonded directly to one another by one or two bonds in a carbon-to-carbon chain,
• d. each said aluminum atom having three bonds and being bonded by at least one of such bonds to one of the carbon atoms in said chain through one of said oxygen atoms intermediately, said carbon atom so bonded having additionally no oxygen atoms double bonded thereto,
• e. being soluble in styrene to a weight percentage at least about equal to the weight percentage of such organoaluminum compound is employed in a given such resin composition,
• f. having a formula weight of from about 200 to 300, and
• g. causing a cloudy dispersion of alumina particles to form when a 10 weight percent solution of such organoaluminum compound in anhydrous benzene is admixed with benzene saturated with distilled water and the resulting mixture is heated for four hours at 60.degree. C.
• the exact amount of said organoaluminum compound present in any given resulting mixed solution being such that said composition remains in a liquid condition, the balance up to 100 weight percent of any given such second solution being said liquid, and
• thereafter permitting the resulting mixed solution to age for a time sufficient to permit said resulting solution to increase in viscosity, the total quantity of said second solution so admixed with said first solution being such as to increase the final viscosity of said resulting solution to a desired extent.