We have developed a one-step process for the synthesis of basic magnesium sulfate (5Mg(OH)2-MgSO4-3H20, abbreviated as 513MOS) whiskers from MgSO4,7H20 and MgO by refluxing at atmospheric pressure. The process sho...We have developed a one-step process for the synthesis of basic magnesium sulfate (5Mg(OH)2-MgSO4-3H20, abbreviated as 513MOS) whiskers from MgSO4,7H20 and MgO by refluxing at atmospheric pressure. The process shows potential for the low-cost mass production of controlled- structure whiskers. Their 0.3-1.0 μm diameter and 40-80 μm length correspond to an aspect ratio of 40-260. The 513MOS whisker morphology is related closely to MgSO4 concentration and reflux time. The optimized MgSO4 concentration is 1.2-1.5 mol/L with a 25-30 h reflux time. X-ray diffractometry revealed that the b-axis is the predominant growth direction of the whiskers. Their growth mechanism is by the relatively slow liquid-phase deposition of Mg2+, OH-, and SO42-. The long reaction time and high MgSO4 concentration are conducive to the formation of 513MOS whiskers under gentle reaction conditions. Porous MgO whiskers with a fibrous structure were obtained after calcination of the 513MOS whiskers at 1020 ℃.展开更多
研究了不饱和聚酯树脂(UP 树脂)/苎麻布/碱式硫酸镁晶须复合材料的力学性能,探讨了苎麻布、晶须加入量对复合材料力学性能及热稳定性的影响,分析了复合材料的冲击断裂形貌。研究表明:当复合材料中苎麻布的质量恒定为 UP 树脂质量的7%时...研究了不饱和聚酯树脂(UP 树脂)/苎麻布/碱式硫酸镁晶须复合材料的力学性能,探讨了苎麻布、晶须加入量对复合材料力学性能及热稳定性的影响,分析了复合材料的冲击断裂形貌。研究表明:当复合材料中苎麻布的质量恒定为 UP 树脂质量的7%时,增加晶须的含量,复合材料的弯曲模量及热稳定性随之增加,弯曲强度逐渐下降,拉伸强度及冲击强度先增加而后降低,当晶须加入量为10%时,拉伸强度及冲击强度均达到最大值,分别为30.16 MPa 和6.07 kJ/m^2;当复合材料中晶须的质量恒定为 UP 树脂质量的10%时,增加复合材料中苎麻布的含量,复合材料的力学性能均随之增加,但热稳定性却下降。UP 树脂/苎麻布/晶须复合材料的断面既有晶须裸露,又有卷曲的苎麻纤维分布,但苎麻布对冲击强度的贡献更突出。展开更多
文摘We have developed a one-step process for the synthesis of basic magnesium sulfate (5Mg(OH)2-MgSO4-3H20, abbreviated as 513MOS) whiskers from MgSO4,7H20 and MgO by refluxing at atmospheric pressure. The process shows potential for the low-cost mass production of controlled- structure whiskers. Their 0.3-1.0 μm diameter and 40-80 μm length correspond to an aspect ratio of 40-260. The 513MOS whisker morphology is related closely to MgSO4 concentration and reflux time. The optimized MgSO4 concentration is 1.2-1.5 mol/L with a 25-30 h reflux time. X-ray diffractometry revealed that the b-axis is the predominant growth direction of the whiskers. Their growth mechanism is by the relatively slow liquid-phase deposition of Mg2+, OH-, and SO42-. The long reaction time and high MgSO4 concentration are conducive to the formation of 513MOS whiskers under gentle reaction conditions. Porous MgO whiskers with a fibrous structure were obtained after calcination of the 513MOS whiskers at 1020 ℃.
文摘研究了不饱和聚酯树脂(UP 树脂)/苎麻布/碱式硫酸镁晶须复合材料的力学性能,探讨了苎麻布、晶须加入量对复合材料力学性能及热稳定性的影响,分析了复合材料的冲击断裂形貌。研究表明:当复合材料中苎麻布的质量恒定为 UP 树脂质量的7%时,增加晶须的含量,复合材料的弯曲模量及热稳定性随之增加,弯曲强度逐渐下降,拉伸强度及冲击强度先增加而后降低,当晶须加入量为10%时,拉伸强度及冲击强度均达到最大值,分别为30.16 MPa 和6.07 kJ/m^2;当复合材料中晶须的质量恒定为 UP 树脂质量的10%时,增加复合材料中苎麻布的含量,复合材料的力学性能均随之增加,但热稳定性却下降。UP 树脂/苎麻布/晶须复合材料的断面既有晶须裸露,又有卷曲的苎麻纤维分布,但苎麻布对冲击强度的贡献更突出。