- Dialkylaminoethyl methacrylate synthesis method
-
The invention discloses a dialkylaminoethyl methacrylate synthesis method, which comprises: adding methyl methacrylate, dialkylaminoethanol, lithium hydroxide and a polymerization inhibitor to a reaction kettle, heating to a temperature of 75-85 DEGC, carrying out a reaction, controlling the temperature of the tower top at 50-55 DEGC, continuously separating methanol under a negative pressure of 600 mmHg, and stopping the reaction until no methanol is separated; purifying dialkylaminoethyl methacrylate; cooling to a room temperature, and washing with deionized water; and distilling the oil phase to obtain unreacted methyl methacrylate and unreacted dialkylaminoethanol, and carrying out pressure reducing distillation to obtain the product. According to the present invention, by using lithium hydroxide as the catalyst, the product yield (of more than 93.5%) and the product purity (of more than 99.0%) are high, the catalyst consumption is low, the price of the catalyst is low, the reaction is fast and can be performed at the low temperature, and the polymerization of methyl methacrylate and the product during the reaction and the separation can be effectively prevented.
- -
-
Paragraph 0021; 0022; 0023; 0024; 0030-0049
(2019/01/08)
-
- Improved preparation method of dialkylaminoethyl methacrylate
-
The invention discloses an improved method for synthesizing dialkylaminoethyl methacrylate by using methyl methacrylate and dialkylamino alcohol as raw materials through ester exchange. According to the method, n-alkane is used as a methanol-carrying solvent, and a water diverter is adopted to constantly separate methanol out of a reaction system. The method includes: adding methyl methacrylate, dialkylamino alcohol, n-alkane and a small amount of polymerization inhibitor into a reaction kettle of a water diversion device, heating to 65-73 DEG C, constantly separating out methanol, and stopping reaction (about 5h) when no methanol is separated out; cooling to room temperature, and using deionized water for washing; distilling off n-alkane and unreacted methyl methacrylate and dialkylamino alcohol from an oil phase, and depressurizing to distill off a product. The method has the advantages that compared with conventional rectification for separating methanol, esterification equipment is simple, and reaction temperature is lowered obviously, so that polymerization of dialkylaminoethyl methacrylate and the product in the process of reaction can be prevented effectively.
- -
-
Paragraph 0020; 0021; 0022; 0023; 0024-0028; 0035-0043
(2017/08/29)
-
- Multi-purpose polymers, methods and compositions
-
Disclosed are multi-purpose polymers that are the polymerization product of a monomer mixture comprising at least one amino-substituted vinyl monomer; at least one nonionic vinyl monomer; at least one associative vinyl monomer; at least one semihydrophobic vinyl surfactant monomer; and, optionally, comprising one or more hydroxy-substituted nonionic vinyl monomer, crosslinking monomer, chain transfer agent or polymeric stabilizer. These vinyl addition polymers have a combination of substituents, including amino substituents that provide cationic properties at low pH, hydrophobic substituents, hydrophobically modified polyoxyalkylene substituents, and hydrophilic polyoxyalkylene substituents. The polymers provide surprisingly beneficial rheological properties in acidic aqueous compositions, and are compatible with cationic materials. The multi-purpose polymers are useful in a variety of products for personal care, health care, household care, institutional and industrial care, and industrial applications.
- -
-
-
- Multi-purpose polymers, methods and compositions
-
Disclosed are multi-purpose polymers that are the polymerization product of a monomer mixture comprising at least one amino-substituted vinyl monomer; at least one nonionic vinyl monomer; at least one associative vinyl monomer; at least one semihydrophobic vinyl surfactant monomer; and, optionally, comprising one or more hydroxy-substituted nonionic vinyl monomer, crosslinking monomer, chain transfer agent or polymeric stabilizer. These vinyl addition polymers have a combination of substituents, including amino substituents that provide cationic properties at low pH, hydrophobic substituents, hydrophobically modified polyoxyalkylene substituents, and hydrophilic polyoxyalkylene substituents. The polymers provide surprisingly beneficial Theological properties in acidic aqueous compositions, and are compatible with cationic materials. Additionally, this invention relates to the incorporation of a basic material after the addition of an acidic material to reduce the pH of the composition without negatively impacting the viscosity of the composition. The multi-purpose polymers are useful in a variety of products for personal care, health care, household care, institutional and industrial care, and industrial applications.
- -
-
-
- Producing unsaturated esters by a lanthanide metal alkoxide catalyzed transesterification process
-
There is disclosed a process for producing an unsaturated ester of the formula (3): wherein R1, R2 and R3 independently represent hydrogen, halogen, alkyl, alkenyl and the like and R5 represents alkyl which may be substituted and the like, which process is characterized by subjecting an unsaturated ester of the formula (1): wherein R1, R2 and R3 have the same meaning as previously defined and R4 represents alkyl or phenyl and the like, to a transesterification reaction with a hydroxy compound of the formula (2):R5OH??(2)wherein R5 has the same meaning as previously defined, in the presence of a lanthanoide metal alkoxide.
- -
-
Page column 7
(2008/06/13)
-