Patents by Inventor Quanxing Zhang
Quanxing Zhang has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 11926608Abstract: The invention discloses a synthesis method and device for rapidly producing lactide at high yield. The method comprises: adding a single component of lactic acid or two components of lactic acid and catalyst, passing the mixture through a mixer to enter an oligomer preparation system, increasing a residence time through bottom circulation, synthesizing oligomeric lactic acid, and passing a gas-phase component through a rectification system. With the adoption of the device, the lactide is capable of being efficiently synthesized, crude lactide with a yield of 94% to 98% is capable of being obtained.Type: GrantFiled: March 4, 2021Date of Patent: March 12, 2024Assignees: NANJING UNIVERSITY, NANJING QUANKAI RESEARCH INSTITUTE OF BIOMATERIALS CO., LTD.Inventors: Wei Jiang, Yunbiao Qi, Ping Sun, Wei Huang, Aimin Li, Quanxing Zhang
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Publication number: 20210188799Abstract: The invention discloses a synthesis method and device for rapidly producing lactide at high yield. The method comprises: adding a single component of lactic acid or two components of lactic acid and catalyst, passing the mixture through a mixer to enter an oligomer preparation system, increasing a residence time through bottom circulation, synthesizing oligomeric lactic acid, and passing a gas-phase component through a rectification system. With the adoption of the device, the lactide is capable of being efficiently synthesized, crude lactide with a yield of 94% to 98% is capable of being obtained.Type: ApplicationFiled: March 4, 2021Publication date: June 24, 2021Inventors: Wei JIANG, Yunbiao QI, Ping SUN, Wei HUANG, Aimin LI, Quanxing ZHANG
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Patent number: 10570111Abstract: A method of purifying a cyclic ester, the method including: granulating a crude cyclic ester, an average particle size of resulting granules being 0.05-1.00 mm; adding the granules to 0-4° C. water to yield a mixture, a mass ratio of the water to the granules being (0.5-2):1; stirring the mixture, and performing solid-liquid separation on the mixture; repeating the stirring and solid-liquid separation for 1-4 times, to yield a purified cyclic ester; drying the purified cyclic ester at 0-4° C. and at an absolute pressure of less than or equal to 10 pascal for 4-6 hours, and continually drying the purified cyclic ester at 40-60° C. and at an absolute pressure of less than or equal to 5 pascal for 1-2 hours.Type: GrantFiled: January 17, 2019Date of Patent: February 25, 2020Assignee: NANJING UNIVERSITYInventors: Hong Li, Quanxing Zhang, Jiaye Sheng, Na Cheng, Wei Huang, Wei Jiang, Aimin Li
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Publication number: 20190194387Abstract: A method of preparing glycolide, the method including dehydrative oligomerization and catalytic depolymerization. The dehydrative oligomerization includes stepwise heating a glycolic acid aqueous solution from room temperature to a temperature of between 200 and 210° C., and maintaining the temperature at each corresponding temperature stage, to yield an oligoglycolic acid. The catalytic depolymerization includes adding a binary complex catalytic system to the oligoglycolic acid to yield a reactant mixture, stepwise heating the reactant mixture from room temperature to a temperature of between 280 and 285° C., and maintaining the temperature at each corresponding temperature stage.Type: ApplicationFiled: March 5, 2019Publication date: June 27, 2019Inventors: Hong LI, Quanxing ZHANG, Jiaye SHENG, Wei HUANG, Wei JIANG, Aimin LI, Bingcai PAN
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Publication number: 20190152939Abstract: A method of purifying a cyclic ester, the method including: granulating a crude cyclic ester, an average particle size of resulting granules being 0.05-1.00 mm; adding the granules to 0-4° C. water to yield a mixture, a mass ratio of the water to the granules being (0.5-2):1; stirring the mixture, and performing solid-liquid separation on the mixture; repeating the stirring and solid-liquid separation for 1-4 times, to yield a purified cyclic ester; drying the purified cyclic ester at 0-4° C. and at an absolute pressure of less than or equal to 10 pascal for 4-6 hours, and continually drying the purified cyclic ester at 40-60° C. and at an absolute pressure of less than or equal to 5 pascal for 1-2 hours.Type: ApplicationFiled: January 17, 2019Publication date: May 23, 2019Inventors: Hong LI, Quanxing ZHANG, Jiaye SHENG, Na CHENG, Wei HUANG, Wei JIANG, Aimin LI
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Patent number: 9896539Abstract: A method for synthesizing poly(butylene adipate-co-terephthalate) by combination of melt and solid state polycondensation using an organic guanidine as a main catalyst. The ternary catalyst system includes a main catalyst, a first cocatalyst, and a second cocatalyst. The main catalyst is organic guanidine; the first cocatalyst is titanate ester or zirconate ester; and the second cocatalyst is metallic oxide. The method includes: 1) adding 1,4-butanediol (BDO), adipic acid (AA), terephthalic acid (TA), and a ternary catalyst system to a reaction still; conducting an oligo-polycondensation to yield a oligomer having the weight average molecular weight (Mw) of between 3.0×103 and 4.0×103; allowing the oligomer to perform a melt polycondensation (MP) to yield a prepolymer with medium Mw of between 1.5×104 and 3.0×104; and 2) crushing the solid prepolymer into granules of 30-40 meshes, and then allowing the granules to undergo solid state polycondensation to yield the final PBAT product.Type: GrantFiled: September 12, 2016Date of Patent: February 20, 2018Assignee: NANJING UNIVERSITYInventors: Hong Li, Quanxing Zhang, Xiangqian Sun, Yunlong Xu, Wei Huang, Aimin Li
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Patent number: 9845377Abstract: A method for preparing high molecular weight poly(L-lactic acid) with high performance, including: a) providing a biogenic guanidine (BG) as a catalyst, and a nontoxic acid salt of an essential metal trace element as an activator (Act), and adding the catalyst, the activator, and L-lactide monomer to a polymerization reactor; b) evacuating under vacuum and charging the polymerization reactor with nitrogen for three consecutive times to remove air, and allowing the L-lactide monomer to undergo bulk polymerization under vacuum. The bulk polymerization includes a first reaction stage and a second reaction stage, which are separately carried out at different temperatures, pressures, and reaction times.Type: GrantFiled: September 14, 2015Date of Patent: December 19, 2017Assignee: NANJING UNIVERSITYInventors: Hong Li, Quanxing Zhang, Xupeng Zong, Aimin Li, Wei Huang, Wei Jiang
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Patent number: 9688811Abstract: A method for synthesizing poly(butylene succinate) (PBS) having a weight average molecular weight (Mw) equal to or larger than 1.4×105. The method employs biogenic guanidine (BG) as the main catalyst and includes: a) adding succinic acid (SA), 1.4-butanediol (BDO), and biogenic guanidine to a reactor, heating the reactor to a temperature of between 180 and 200° C. and conducting the esterification between succinic acid and 1.4-butanediol for 2 to 3 hours under atmospheric pressure until all of the water is distilled or boiled off; and b) adding a first cocatalyst, a second cocatalyst, and a third cocatalyst to the reactor, adjusting the absolute pressure in the reactor to be between 0.5 and 3 torr, and polycondensing the mixture in the reactor at the temperature between 210 and 230° C. over 20 to 30 hours.Type: GrantFiled: September 12, 2016Date of Patent: June 27, 2017Assignee: NANJING UNIVERSITYInventors: Hong Li, Quanxing Zhang, Yiting Song, Xiangqian Sun, Wei Huang, Aimin Li
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Patent number: 9637590Abstract: A method for synthesizing polylactide (PLA). The method employs RCOOCG, a nontoxic carboxylate of cyclic guanidine (CG), as a catalyst and non-toxic organic alcohol R?OH as an initiator to catalyze/initiate a living ring-opening polymerization of lactide (LA). The method includes: 1) adding monomer LA, the catalyst RCOOCG, and the initiator R?OH to a reaction still, where an initial molar ratio of the monomer to the catalyst is [LA]0/[RCOOCG]0=1000-1500:1, an initial molar amount [R?OH]0 of the initiator R?OH is determined by a number average molecular weight (Mn) of a target product PLA; 2) removing air in the reaction still, sealing the reaction still after a pressure in the reaction still is constant at between 1.0 and 0.1 torr; stirring and heating the reaction still in 30 to 40 minutes to a temperature between 95 and 96° C.; and allowing reactants in the reaction still to polymerization.Type: GrantFiled: September 19, 2016Date of Patent: May 2, 2017Assignee: NANJING UNIVERSITYInventors: Hong Li, Quanxing Zhang, Wei Huang, Jiaye Sheng, Aimin Li
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Patent number: 9630942Abstract: A technological method for synthesizing optically pure L-/D-lactide by using a biogenic guanidine catalysis method. The method of the present invention comprises: by using biogenic guanidine creatinine (CR) as a catalyst and L-/D-lactic acid (90% of mass content) as a raw material, synthesizing optically pure L-/D-lactide by using a reactive reduced pressure distillation catalysis method.Type: GrantFiled: August 17, 2013Date of Patent: April 25, 2017Assignee: Nanjing UniversityInventors: Hong Li, Quanxing Zhang, Na Cheng, Tianrong Zhang, Wei Jiang, Wei Huang, Bingcai Pan
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Publication number: 20170009011Abstract: A method for synthesizing polylactide (PLA). The method employs RCOOCG, a nontoxic carboxylate of cyclic guanidine (CG), as a catalyst and non-toxic organic alcohol R?OH as an initiator to catalyze/initiate a living ring-opening polymerization of lactide (LA). The method includes: 1) adding monomer LA, the catalyst RCOOCG, and the initiator R?OH to a reaction still, where an initial molar ratio of the monomer to the catalyst is [LA]0/[RCOOCG]0=1000-1500:1, an initial molar amount [R?OH]0 of the initiator R?OH is determined by a number average molecular weight (Mn) of a target product PLA; 2) removing air in the reaction still, sealing the reaction still after a pressure in the reaction still is constant at between 1.0 and 0.1 torr; stirring and heating the reaction still in 30 to 40 minutes to a temperature between 95 and 96° C.; and allowing reactants in the reaction still to polymerization.Type: ApplicationFiled: September 19, 2016Publication date: January 12, 2017Inventors: Hong LI, Quanxing ZHANG, Wei HUANG, Jiaye SHENG, Aimin LI
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Publication number: 20160376403Abstract: A method for synthesizing poly(butylene adipate-co-terephthalate) by combination of melt and solid state polycondensation using an organic guanidine as a main catalyst. The ternary catalyst system includes a main catalyst, a first cocatalyst, and a second cocatalyst. The main catalyst is organic guanidine; the first cocatalyst is titanate ester or zirconate ester; and the second cocatalyst is metallic oxide. The method includes: 1) adding 1,4-butanediol (BDO), adipic acid (AA), terephthalic acid (TA), and a ternary catalyst system to a reaction still; conducting an oligo-polycondensation to yield a oligomer having the weight average molecular weight (Mw) of between 3.0×103 and 4.0×103; allowing the oligomer to perform a melt polycondensation (MP) to yield a prepolymer with medium Mw of between 1.5×104 and 3.0×104; and 2) crushing the solid prepolymer into granules of 30-40 meshes, and then allowing the granules to undergo solid state polycondensation to yield the final PBAT product.Type: ApplicationFiled: September 12, 2016Publication date: December 29, 2016Inventors: Hong LI, Quanxing ZHANG, Xiangqian SUN, Yunlong XU, Wei HUANG, Aimin LI
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Publication number: 20160376402Abstract: A method for synthesizing poly(butylene succinate) (PBS) having a weight average molecular weight (Mw) equal to or larger than 1.4×105. The method employs biogenic guanidine (BG) as the main catalyst and includes: a) adding succinic acid (SA), 1.4-butanediol (BDO), and biogenic guanidine to a reactor, heating the reactor to a temperature of between 180 and 200° C. and conducting the esterification between succinic acid and 1.4-butanediol for 2 to 3 hours under atmospheric pressure until all of the water is distilled or boiled off; and b) adding a first cocatalyst, a second cocatalyst, and a third cocatalyst to the reactor, adjusting the absolute pressure in the reactor to be between 0.5 and 3 torr, and polycondensing the mixture in the reactor at the temperature between 210 and 230° C. over 20 to 30 hours.Type: ApplicationFiled: September 12, 2016Publication date: December 29, 2016Inventors: Hong LI, Quanxing ZHANG, Yiting SONG, Xiangqian SUN, Wei HUANG, Aimin LI
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Patent number: 9469724Abstract: A method for synthesizing poly(butylene succinate-co-butylene adipate) (PBSA), including: a) adding raw materials including succinic acid, adipic acid, and 1,4-butanediol into a reaction still; increasing the temperature in the reaction still to 130° C., and stirring the raw materials, then keeping the temperature in the reaction still at 170-200° C., and dehydrating for 1-3 hours at atmospheric pressure, to yield an oligomer of PBSA; and b) decreasing the temperature of the reaction still to 100° C., and adding a composite catalyst system, the total addition of the composite catalyst system accounting for one ten-thousandth to one ten-millionth of a total weight percentage of the raw materials; uniformly stiffing and mixing the composite catalyst system and reactants, slowly vacuum pumping the reaction still, heating the reaction still to a temperature of 200-240° C. and allowing the composite catalyst system and the reactants to react for 10-20 hrs.Type: GrantFiled: December 10, 2015Date of Patent: October 18, 2016Assignee: NANJING UNIVERSITYInventors: Hong Li, Quanxing Zhang, Na Cheng, Tianrong Zhang, Wei Jiang, Bingcai Pan
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Publication number: 20160168316Abstract: A method for preparing high molecular weight poly(L-lactic acid) with high performance, including: a) providing a biogenic guanidine (BG) as a catalyst, and a nontoxic acid salt of an essential metal trace element as an activator (Act), and adding the catalyst, the activator, and L-lactide monomer to a polymerization reactor; b) evacuating under vacuum and charging the polymerization reactor with nitrogen for three consecutive times to remove air, and allowing the L-lactide monomer to undergo bulk polymerization under vacuum. The bulk polymerization includes a first reaction stage and a second reaction stage, which are separately carried out at different temperatures, pressures, and reaction times.Type: ApplicationFiled: September 14, 2015Publication date: June 16, 2016Inventors: Hong LI, Quanxing ZHANG, Xupeng ZONG, Aimin LI, Wei HUANG, Wei JIANG
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Publication number: 20160096917Abstract: A method for synthesizing poly(butylene succinate-co-butylene adipate) (PBSA), including: a) adding raw materials including succinic acid, adipic acid, and 1,4-butanediol into a reaction still; increasing the temperature in the reaction still to 130° C., and stiffing the raw materials, then keeping the temperature in the reaction still at 170-200° C., and dehydrating for 1-3 hours at atmospheric pressure, to yield an oligomer of PBSA; and b) decreasing the temperature of the reaction still to 100° C., and adding a composite catalyst system, the total addition of the composite catalyst system accounting for one ten-thousandth to one ten-millionth of a total weight percentage of the raw materials; uniformly stiffing and mixing the composite catalyst system and reactants, slowly vacuum pumping the reaction still, heating the reaction still to a temperature of 200-240° C. and allowing the composite catalyst system and the reactants to react for 10-20 hrs.Type: ApplicationFiled: December 10, 2015Publication date: April 7, 2016Inventors: Hong LI, Quanxing ZHANG, Na CHENG, Tianrong ZHANG, Wei JIANG, Bingcai PAN
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Publication number: 20160039782Abstract: A technological method for synthesizing optically pure L-/D-lactide by using a biogenic guanidine catalysis method. The method of the present invention comprises: by using biogenic guanidine creatinine (CR) as a catalyst and L-/D-lactic acid (90% of mass content) as a raw material, synthesizing optically pure L-/D-lactide by using a reactive reduced pressure distillation catalysis method.Type: ApplicationFiled: August 17, 2013Publication date: February 11, 2016Inventors: Hong Li, Quanxing Zhang, Na Cheng, Tianrong Zhang, Wei Jiang, Wei Huang, Bingcai Pan
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Patent number: 9138737Abstract: A method for regulating the distribution of metallic nanoparticles within the resin support is provided. This method uses the ion exchange or absorption resin bearing basic functional groups as the support; firstly introducing the metal in the form of anionic complexes onto the resin support through the ion exchange process, then realizing the purpose of regulating the distribution of the metal and its compound within the resin support by means of changing the concentration of the reductive or deposition agent in water solution and the reaction time. The regulated distribution of metallic nanoparticles within the resin support is in the form of rings with different depths and densities.Type: GrantFiled: May 3, 2011Date of Patent: September 22, 2015Assignee: NANJING UNIVERSITYInventors: Bingcai Pan, Zhenmao Jiang, Weiming Zhang, Lu Lv, Yingmei Xie, Quanxing Zhang
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Patent number: 9062006Abstract: Disclosed is a high molecular weight polylactic acid synthesized by using a method for synthesizing and catalytically-polycondensing bionic creatinine-guanidinium chloride. Creatinine is used as the material in a reaction with aqueous hydrochloric acid to synthesize a bionic creatinine-guanidinium salt catalyst, creatinine-guanidinium chloride (CR.Cl). The creatinine-guanidinium chloride synthesized is used as a catalyst, an industrial grade lactic acid (LA, 85% to 90%, aqueous solution) is used as a monomer, a solvent-free two-step polycondensation method is used to synthesize and afford metal-free and toxic residue-free polylactic acid featuring high biological safety and high molecular weight.Type: GrantFiled: November 2, 2011Date of Patent: June 23, 2015Assignee: NANJING UNIVERSITYInventors: Hong Li, Quanxing Zhang, Wei Huang, Wei Jiang, Xupeng Zong, Bingcai Pan
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Patent number: 9062159Abstract: A method for synthesizing a medical grade biodegradable material, poly(lactic-co-glycolic acid), copolycondensation of lactic acid and glycolic acid catalyzed by biomass creatinine. The present invention uses commercialized creatinine (a type of biomaterial organic guanidine compounds—the arginine metabolite creatinine (CR) in human body) as the catalyst and industrial lactic acid (LA, mass content 85%, aqueous solution) and glycolic acid (GA, 95%) as the monomer to synthesize the high biosafety of medical poly(lactic-co-glycolic acid) in terms of two steps polycondensation without solvent.Type: GrantFiled: November 3, 2011Date of Patent: June 23, 2015Assignee: Nanjing UniversityInventors: Hong Li, Quanxing Zhang, Wei Jiang, Bingcai Pan