Surface modification of calcium carbonate particles using sodium stearate(SDS) as a modification agent incorporated with the simultaneous wet ultra-fine grinding in the laboratory stirred mill was investigated. The ph...Surface modification of calcium carbonate particles using sodium stearate(SDS) as a modification agent incorporated with the simultaneous wet ultra-fine grinding in the laboratory stirred mill was investigated. The physical properties and application properties of modified calcium carbonate were measured and evaluated. The action mechanism between SDS and calcium carbonate in the modification was studied by infrared spectrometry(IR) and X-ray photoelectron energy spectroscopy(XPS). The results indicate that the crushing mechanic force intensity can obviously influence the modification effect of calcium carbonate because of mechano-chemical effect. The hydrophilic surface of calcium carbonate is turned into hydrophobic after modification. The properties of polyethylene(PE) filled by modified calcium carbonate powder is markedly improved. And the adsorption of SDS could occur by chemical reaction with calcium carbonate surface.展开更多
Calcium carbonate,which is widely employed as a filler added into the polymer matrix,has large numbers of applications owing to the excellent properties such as low cost,non-toxicity,high natural reserves and biocompa...Calcium carbonate,which is widely employed as a filler added into the polymer matrix,has large numbers of applications owing to the excellent properties such as low cost,non-toxicity,high natural reserves and biocompatibility.Nevertheless,in order to obtain the good filling effect,calcium carbonate needs to be surface modified by organic molecules so as to enhance the dispersion and compatibility within the composites.This review paper systematically introduces the theory,methods,and applications progress of calcium carbonate with surface modification.Additionally,the key factors that affect the properties of the composites as well as the current difficulties and challenges are highlighted.The current research progress and potential application prospects of calcium carbonate in the fields of plastics,rubber,paper,medicine and environmental protection are discussed as well.Generally,this review can provide valuable reference for the modification and comprehensive utilization of calcium carbonate.展开更多
A kind of modifier was synthesized to modify the surface of nanometer calcium carbonate (abbreviated as nano-CaCO3), which is used in architectural coatings. The modification technology of the nano-CaCO3 was studied...A kind of modifier was synthesized to modify the surface of nanometer calcium carbonate (abbreviated as nano-CaCO3), which is used in architectural coatings. The modification technology of the nano-CaCO3 was studied through orthogonal experimental methods. The factors studied were rotation speed, modifier dosage, emulsification temperature, emulsification time and heat aging time after emulsification. Optimized conditions for modification of the surface were: rotation speed 16000 r/min; modifier dosage 3%; emulsification temperature 75 ℃; emulsification time 60 min and aging time 40 min. The modified nano-CaCO3 was also studied by size-distribution measurements, transmission electron microscopy, infrared spectroscopy and thermal analysis. The results show that the size distribution of the modified nano-CaCO3 is uniform and that there are chemi-sorption and physi-sorption between the nano-CaCO3 and the modifier. Compared to traditional architectural coatings without nano-CaCO3, the nanometer composite coatings are obviously improved in respect to dirt resistance, scrub resistance, thixotropy, water resistance, alkalinity resistance and aging resistance.展开更多
Five 1,3diisopropoxyaloxanes,i.e.,(PriO)RO2AlOAlO2R(OPri)_C18H35(),_C9H16CH=CHC7H15(),_P(OCH2(C2H5)CHC4H9)2(),and_C12H23(),respectively]were synthesized by the hydrolysiscondensation of aluminium isopropoxide with wat...Five 1,3diisopropoxyaloxanes,i.e.,(PriO)RO2AlOAlO2R(OPri)_C18H35(),_C9H16CH=CHC7H15(),_P(OCH2(C2H5)CHC4H9)2(),and_C12H23(),respectively]were synthesized by the hydrolysiscondensation of aluminium isopropoxide with water and exchange reaction with relevant acids.They were characterized by elemental analysis,determination of molecular weight,IR,and 27Al NMR.The results show that the coordination number of Al atom in the compounds is 5 and they exist in monomers in benzene.The analyses of TG/DTG and DTA indicated that both the thermal hydrolysis stability and thermal stability of these compounds are in the following order:<<<.The viscosity determinations of light calcium carbonate(LCaCO3)/liquid paraffin suspension systems demonstrated that they had an excellent modification effect on the surface of LCaCO3 filler and the amount needed to form a monomolecular film on the surface of LCaCO3 particles is in the order.展开更多
Nanometer calcium carbonate was modified with Frechet type polyether dendrons bearing a COOH group at thefocal point by a wet-coating technique in dichloromethane at room temperature. The interaction between CaCO;and ...Nanometer calcium carbonate was modified with Frechet type polyether dendrons bearing a COOH group at thefocal point by a wet-coating technique in dichloromethane at room temperature. The interaction between CaCO;and thedendritic modifier was proven by IR and mass spectroscopy of the modified CaCO;after thorough extraction withdichloromethane. The amount of tightly bonded organic modifier was estimated by TGA. It was shown that the amount ofbonded molecules decreased with increasing generation number due to the larger number of branches. Compared tounmodified CaCO;, the modified CaCO;possess different dispersibility in water and in organic solvents.展开更多
尽可能低的吸油值是人造石材对重质碳酸钙填料的主要技术指标要求之一。选取聚乙二醇-200、一缩二乙二醇、三乙醇胺和氨基硅油-804为改性剂,采用干法对重质碳酸钙填料进行表面改性,以吸油值为表征手段,研究了改性剂品种及其用量对重质...尽可能低的吸油值是人造石材对重质碳酸钙填料的主要技术指标要求之一。选取聚乙二醇-200、一缩二乙二醇、三乙醇胺和氨基硅油-804为改性剂,采用干法对重质碳酸钙填料进行表面改性,以吸油值为表征手段,研究了改性剂品种及其用量对重质碳酸钙填料吸油值影响的规律,并结合红外光谱分析和热重分析对改性机理进行了讨论。结果表明:改性样品的吸油值随改性剂用量的增大而下降,采用氨基硅油-804改性剂且用量为1.00%时,改性样品的吸油值最低,达到0.115 m L/g,改性后样品的热稳定性最好,热分解温度为325℃;4种改性剂均与重质碳酸钙粉体表面的官能团羟基发生了化学键合作用。展开更多
基金Project(2032008) supported by the Natural Science Foundation of Beijing City, China
文摘Surface modification of calcium carbonate particles using sodium stearate(SDS) as a modification agent incorporated with the simultaneous wet ultra-fine grinding in the laboratory stirred mill was investigated. The physical properties and application properties of modified calcium carbonate were measured and evaluated. The action mechanism between SDS and calcium carbonate in the modification was studied by infrared spectrometry(IR) and X-ray photoelectron energy spectroscopy(XPS). The results indicate that the crushing mechanic force intensity can obviously influence the modification effect of calcium carbonate because of mechano-chemical effect. The hydrophilic surface of calcium carbonate is turned into hydrophobic after modification. The properties of polyethylene(PE) filled by modified calcium carbonate powder is markedly improved. And the adsorption of SDS could occur by chemical reaction with calcium carbonate surface.
基金Project(AA18242008)supported by the Guangxi Science&Technology Major Project,ChinaProject(HZXYKFKT201904)supported by the Opening Project of Guangxi Key Laboratory of Calcium Carbonate Resources Comprehensive Utilization,China。
文摘Calcium carbonate,which is widely employed as a filler added into the polymer matrix,has large numbers of applications owing to the excellent properties such as low cost,non-toxicity,high natural reserves and biocompatibility.Nevertheless,in order to obtain the good filling effect,calcium carbonate needs to be surface modified by organic molecules so as to enhance the dispersion and compatibility within the composites.This review paper systematically introduces the theory,methods,and applications progress of calcium carbonate with surface modification.Additionally,the key factors that affect the properties of the composites as well as the current difficulties and challenges are highlighted.The current research progress and potential application prospects of calcium carbonate in the fields of plastics,rubber,paper,medicine and environmental protection are discussed as well.Generally,this review can provide valuable reference for the modification and comprehensive utilization of calcium carbonate.
文摘A kind of modifier was synthesized to modify the surface of nanometer calcium carbonate (abbreviated as nano-CaCO3), which is used in architectural coatings. The modification technology of the nano-CaCO3 was studied through orthogonal experimental methods. The factors studied were rotation speed, modifier dosage, emulsification temperature, emulsification time and heat aging time after emulsification. Optimized conditions for modification of the surface were: rotation speed 16000 r/min; modifier dosage 3%; emulsification temperature 75 ℃; emulsification time 60 min and aging time 40 min. The modified nano-CaCO3 was also studied by size-distribution measurements, transmission electron microscopy, infrared spectroscopy and thermal analysis. The results show that the size distribution of the modified nano-CaCO3 is uniform and that there are chemi-sorption and physi-sorption between the nano-CaCO3 and the modifier. Compared to traditional architectural coatings without nano-CaCO3, the nanometer composite coatings are obviously improved in respect to dirt resistance, scrub resistance, thixotropy, water resistance, alkalinity resistance and aging resistance.
文摘Five 1,3diisopropoxyaloxanes,i.e.,(PriO)RO2AlOAlO2R(OPri)_C18H35(),_C9H16CH=CHC7H15(),_P(OCH2(C2H5)CHC4H9)2(),and_C12H23(),respectively]were synthesized by the hydrolysiscondensation of aluminium isopropoxide with water and exchange reaction with relevant acids.They were characterized by elemental analysis,determination of molecular weight,IR,and 27Al NMR.The results show that the coordination number of Al atom in the compounds is 5 and they exist in monomers in benzene.The analyses of TG/DTG and DTA indicated that both the thermal hydrolysis stability and thermal stability of these compounds are in the following order:<<<.The viscosity determinations of light calcium carbonate(LCaCO3)/liquid paraffin suspension systems demonstrated that they had an excellent modification effect on the surface of LCaCO3 filler and the amount needed to form a monomolecular film on the surface of LCaCO3 particles is in the order.
基金This work was supported by Tsinghua-Zhongda Postdoctoral Science Foundation and China Postdoctoral Science Foundation.
文摘Nanometer calcium carbonate was modified with Frechet type polyether dendrons bearing a COOH group at thefocal point by a wet-coating technique in dichloromethane at room temperature. The interaction between CaCO;and thedendritic modifier was proven by IR and mass spectroscopy of the modified CaCO;after thorough extraction withdichloromethane. The amount of tightly bonded organic modifier was estimated by TGA. It was shown that the amount ofbonded molecules decreased with increasing generation number due to the larger number of branches. Compared tounmodified CaCO;, the modified CaCO;possess different dispersibility in water and in organic solvents.
文摘尽可能低的吸油值是人造石材对重质碳酸钙填料的主要技术指标要求之一。选取聚乙二醇-200、一缩二乙二醇、三乙醇胺和氨基硅油-804为改性剂,采用干法对重质碳酸钙填料进行表面改性,以吸油值为表征手段,研究了改性剂品种及其用量对重质碳酸钙填料吸油值影响的规律,并结合红外光谱分析和热重分析对改性机理进行了讨论。结果表明:改性样品的吸油值随改性剂用量的增大而下降,采用氨基硅油-804改性剂且用量为1.00%时,改性样品的吸油值最低,达到0.115 m L/g,改性后样品的热稳定性最好,热分解温度为325℃;4种改性剂均与重质碳酸钙粉体表面的官能团羟基发生了化学键合作用。