This paper deals with the preparation of cationic starch with high degree of substitute by dry-process. The corn starch and the alkali catalyst are mixed in the mixer, then added the cationic etherifying agent (3-chlo...This paper deals with the preparation of cationic starch with high degree of substitute by dry-process. The corn starch and the alkali catalyst are mixed in the mixer, then added the cationic etherifying agent (3-chloro-2-hydroxypropyltrimethylammonium chloride). The reacting time is for 5 hours at the temperature of 70℃. The cationic starch with high degree of substitution is used as anionic charge neutralizing agents to improve filler retention in wet-end section of papermaking machine.展开更多
The tacticity of vinyl polymers is a key factor affecting the properties of materials.Recently,organic Brønsted acids have been demonstrated as effective catalysts for the development of highly stereoselective ca...The tacticity of vinyl polymers is a key factor affecting the properties of materials.Recently,organic Brønsted acids have been demonstrated as effective catalysts for the development of highly stereoselective cationic reversible addition-fragmentation chain transfer(RAFT)polymerizations of vinyl ethers,in which the use of RAFT agents could allow the control the molecular weight and tacticity of polymer products simultaneously.However,the effect of RAFT agents on the tacticity-regulation remains elusive and lacks of investigation.In this study,we synthesized four types of RAFT agents and evaluated their influence in the stereoselective cationic polymerization of isobutyl vinyl ether in the presence of PADI as a Brønsted acid catalyst,which unveils that the Z group of RAFT agents could not only affect the polydispersity of the products,but also exert a profound effect on the stereoselectivity.After extensive screening of the RAFT agents,high stereoregularity(isotacticity,90%m)was obtained when using dithiocarbonate ester-type RAFT agents with a benzyloxy Z group.展开更多
Introduction Cationic starches are a series of products of which various sorts with different properties and usages can all be produced via cationic reactions by using different types of etherification agents under di...Introduction Cationic starches are a series of products of which various sorts with different properties and usages can all be produced via cationic reactions by using different types of etherification agents under different conditions. As an additive and strengthening agent,展开更多
Cationic polymer drilling fluid (CPDF) is a new water base drilling fluid in which high molecular weight (HMW) cationic polymer (CPAM) is an encapsulating and flocculating agent and organic quaternary ammonium compoun...Cationic polymer drilling fluid (CPDF) is a new water base drilling fluid in which high molecular weight (HMW) cationic polymer (CPAM) is an encapsulating and flocculating agent and organic quaternary ammonium compound (NW-1) acts as shale inhibitor. This paper describes the experimental results of cuttings recovery, particle size distribution layer spacing and Zeta potential, and discusses the inhibition of CPDF system and its major additives. The advantages of CPDF will be proved by its application in well LX-2.展开更多
Cationic polymer fluid loss additive (CPFL) was prepared by using the reaction of 2,3-epoxypropy- ltrimethyl ammonium chloride (EPTMAC) (as cationic reagent) with the amide group in the molecular structure of th...Cationic polymer fluid loss additive (CPFL) was prepared by using the reaction of 2,3-epoxypropy- ltrimethyl ammonium chloride (EPTMAC) (as cationic reagent) with the amide group in the molecular structure of the sodium salt of partially hydrolyzed polyacrylonitrile fibers (HPAN-Na). The chemical reaction was determined by studying the infrared absorption peaks of the materials and the products. The results proved that the cationic groups of EPTMAC were successfully grafted onto the HPAN molecular chain. The composition of the molecular chain of the product CPFL was determined by investigation and calculation of the elemental analysis results of the grafted HPAN and the final reaction product CPFL. The drilling fluid performance was evaluated, and the result showed that when the cation content was more than 0.27 mmol/g, the drilling fluid would have good resistance to fluid loss and to pollution from calcium chloride.展开更多
In this contribution,we report the cooperative structure-directing effect of choline hydroxide and aluminosilicate*BEA zeolite in the synthesis of aluminogermanosilicate IWR zeolites for the first time.*BEA zeolites,a...In this contribution,we report the cooperative structure-directing effect of choline hydroxide and aluminosilicate*BEA zeolite in the synthesis of aluminogermanosilicate IWR zeolites for the first time.*BEA zeolites,at variance with any other aluminosilicate zeolites,can serve as heterogeneous seeds for the growth of IWR zeolites and play a cooperative structure-directing role.The crystallization process was investigated using multiple techniques to characterize a series of solid products obtained with various crystallization times.The experiments clearly showed the dissolution of the*BEA zeolite and of an intermediate CDO-type structure.A plausible mechanism for the novel cooperative synthesis has been proposed.The crystallization of the IWR zeolite involves several steps,among which the crucial one is believed to be the reassembly of the building units produced from the decomposition of*BEA zeolite seeds,induced by choline molecules.Having similar structure and common building units(four-,five-,and six-membered rings)with the IWR zeolite,the*BEA zeolite is capable of promoting the reassembly of the building units and can thus play a cooperative structure-directing role.By highlighting the cooperative structure-directing effect of organic molecules and heterogeneous seeds,this study opens up new perspectives for the synthesis of target zeolites that are difficult to prepare by traditional methods.This new synthetic route is also expected to shed light on the discovery of novel zeolites.展开更多
To study the effect of free radical photocurable passivation film modified by titanate coupling agent for hot-plated aluminum-zinc plate,trimethylpropane triacrylate(TMPTA)and 2-phenoxyethyl acrylate were used as acti...To study the effect of free radical photocurable passivation film modified by titanate coupling agent for hot-plated aluminum-zinc plate,trimethylpropane triacrylate(TMPTA)and 2-phenoxyethyl acrylate were used as active diluents,a mixture of modified epoxy acrylate and modified polyester acrylate in a certain proportion was used as an oligomer,2-methyl-1-[4-(methylothyl)benzene]-2-morpholine acetone(907)was used as a free radical photoinitiator,isopropyl thioxanthone(ITX)was used as sensitizer,and bis(dioctyl phosphate acyl)titanate ethyltitanate acrylamide chelate(FD-812)was used as corrosion inhibitor modifier.After UV-curing,the passivation film was characterized by neutral salt spray test,electrochemical testing and other methods.The general performance of the passivation film may meet the requirements of downstream users of hot aluminum-zinc steel plate.The neutral salt spray test,electrochemical testing and microscopic surface morphology analysis of passivation film are in agreement.The introduction of titanate components may effectively promote the photocuring of free radicals.There have been few reports on the titanate coupling which is added to UV-curing coating formula.The titanate coupling agent contains acrylamide groups and terminal amine groups,acrylamide group has oligomer and crosslinking monomer,the terminal tertiary amine groups can provide hydrogen protons,reduce oxygen polymerization,and a phosphating film is formed on the surface of the metal substrate to improve the adhesion and corrosion resistance of the coating.展开更多
文摘This paper deals with the preparation of cationic starch with high degree of substitute by dry-process. The corn starch and the alkali catalyst are mixed in the mixer, then added the cationic etherifying agent (3-chloro-2-hydroxypropyltrimethylammonium chloride). The reacting time is for 5 hours at the temperature of 70℃. The cationic starch with high degree of substitution is used as anionic charge neutralizing agents to improve filler retention in wet-end section of papermaking machine.
基金supported by the Recruitment Program of Global Experts of China,the National Natural Science Foundation of China(Nos.21602028 and 22371240)Beijing National Laboratory for Molecular Sciences(No.BNLMS201913)100-Talent program of Fujian,Fuzhou University and Xiamen University.
文摘The tacticity of vinyl polymers is a key factor affecting the properties of materials.Recently,organic Brønsted acids have been demonstrated as effective catalysts for the development of highly stereoselective cationic reversible addition-fragmentation chain transfer(RAFT)polymerizations of vinyl ethers,in which the use of RAFT agents could allow the control the molecular weight and tacticity of polymer products simultaneously.However,the effect of RAFT agents on the tacticity-regulation remains elusive and lacks of investigation.In this study,we synthesized four types of RAFT agents and evaluated their influence in the stereoselective cationic polymerization of isobutyl vinyl ether in the presence of PADI as a Brønsted acid catalyst,which unveils that the Z group of RAFT agents could not only affect the polydispersity of the products,but also exert a profound effect on the stereoselectivity.After extensive screening of the RAFT agents,high stereoregularity(isotacticity,90%m)was obtained when using dithiocarbonate ester-type RAFT agents with a benzyloxy Z group.
文摘Introduction Cationic starches are a series of products of which various sorts with different properties and usages can all be produced via cationic reactions by using different types of etherification agents under different conditions. As an additive and strengthening agent,
文摘Cationic polymer drilling fluid (CPDF) is a new water base drilling fluid in which high molecular weight (HMW) cationic polymer (CPAM) is an encapsulating and flocculating agent and organic quaternary ammonium compound (NW-1) acts as shale inhibitor. This paper describes the experimental results of cuttings recovery, particle size distribution layer spacing and Zeta potential, and discusses the inhibition of CPDF system and its major additives. The advantages of CPDF will be proved by its application in well LX-2.
基金supported by China National High Technology Research and Development Program(863 Program, 2013AA064803)
文摘Cationic polymer fluid loss additive (CPFL) was prepared by using the reaction of 2,3-epoxypropy- ltrimethyl ammonium chloride (EPTMAC) (as cationic reagent) with the amide group in the molecular structure of the sodium salt of partially hydrolyzed polyacrylonitrile fibers (HPAN-Na). The chemical reaction was determined by studying the infrared absorption peaks of the materials and the products. The results proved that the cationic groups of EPTMAC were successfully grafted onto the HPAN molecular chain. The composition of the molecular chain of the product CPFL was determined by investigation and calculation of the elemental analysis results of the grafted HPAN and the final reaction product CPFL. The drilling fluid performance was evaluated, and the result showed that when the cation content was more than 0.27 mmol/g, the drilling fluid would have good resistance to fluid loss and to pollution from calcium chloride.
基金supported by the National Key R&D Program of China(2017YFB0702800)National Natural Science Foundation of China(21802168,21503280,21603277)China Petrochemical Corporation(Sinopec Group)~~
文摘In this contribution,we report the cooperative structure-directing effect of choline hydroxide and aluminosilicate*BEA zeolite in the synthesis of aluminogermanosilicate IWR zeolites for the first time.*BEA zeolites,at variance with any other aluminosilicate zeolites,can serve as heterogeneous seeds for the growth of IWR zeolites and play a cooperative structure-directing role.The crystallization process was investigated using multiple techniques to characterize a series of solid products obtained with various crystallization times.The experiments clearly showed the dissolution of the*BEA zeolite and of an intermediate CDO-type structure.A plausible mechanism for the novel cooperative synthesis has been proposed.The crystallization of the IWR zeolite involves several steps,among which the crucial one is believed to be the reassembly of the building units produced from the decomposition of*BEA zeolite seeds,induced by choline molecules.Having similar structure and common building units(four-,five-,and six-membered rings)with the IWR zeolite,the*BEA zeolite is capable of promoting the reassembly of the building units and can thus play a cooperative structure-directing role.By highlighting the cooperative structure-directing effect of organic molecules and heterogeneous seeds,this study opens up new perspectives for the synthesis of target zeolites that are difficult to prepare by traditional methods.This new synthetic route is also expected to shed light on the discovery of novel zeolites.
基金by the National Basic Research Program of China(2009AA03Z529)。
文摘To study the effect of free radical photocurable passivation film modified by titanate coupling agent for hot-plated aluminum-zinc plate,trimethylpropane triacrylate(TMPTA)and 2-phenoxyethyl acrylate were used as active diluents,a mixture of modified epoxy acrylate and modified polyester acrylate in a certain proportion was used as an oligomer,2-methyl-1-[4-(methylothyl)benzene]-2-morpholine acetone(907)was used as a free radical photoinitiator,isopropyl thioxanthone(ITX)was used as sensitizer,and bis(dioctyl phosphate acyl)titanate ethyltitanate acrylamide chelate(FD-812)was used as corrosion inhibitor modifier.After UV-curing,the passivation film was characterized by neutral salt spray test,electrochemical testing and other methods.The general performance of the passivation film may meet the requirements of downstream users of hot aluminum-zinc steel plate.The neutral salt spray test,electrochemical testing and microscopic surface morphology analysis of passivation film are in agreement.The introduction of titanate components may effectively promote the photocuring of free radicals.There have been few reports on the titanate coupling which is added to UV-curing coating formula.The titanate coupling agent contains acrylamide groups and terminal amine groups,acrylamide group has oligomer and crosslinking monomer,the terminal tertiary amine groups can provide hydrogen protons,reduce oxygen polymerization,and a phosphating film is formed on the surface of the metal substrate to improve the adhesion and corrosion resistance of the coating.