This is an article in the field of mineral processing engineering.Tourmaline has been widely used for its spontaneous polarity,pyroelectric effect,far-infrared radiation and negative-ion release effect.In order to increase its stability in water-based coatings and improve its performance in water-based coatings,in this work,the surface modification of tourmaline with carboxylated nanolocellulose(C-CNF)was studied and optimized.The test results show that the performance of modified tourmaline was optimal while the addition of C-CNF was 2 g,solid-to-liquid ratio 1:5,and reacted 2h at 50 ℃,its turbidity reached 1361 ntu,contact angle to 53°.It was found that C-CNF was successfully grafted to the tourmaline surface by means of characterization of the modified tourmaline,and the dispersion of the modified tourmaline in the aqueous medium was better improved.

This is an article in the field of mineral materials.The tourmaline powder was modified with silane coupling agent KH-171,and the process conditions were optimized with the parameters of contact angle and turbidity of the modified product in liquid paraffin.The test results showed that the contact angle of the resulting modified tourmaline reached 133 ℃ when reacted at 60 ℃ for 2 h at a system pH value of 9,a dosage of modifier KH-171 of 2 mL,and an alcohol-to-water ratio of 1:5,showing excellent hydrophobic properties.The modified tourmaline was characterized by IR,SEM and XRD.The results showed that the organic functional groups with carbon-carbon double bonds were successfully connected to the surface of tourmaline without changing the original crystal structure,but the agglomeration of tourmaline reduced effectively and showed better dispersion performance.

以聚醚三醇330N和聚碳酸酯二醇(PCDL)混合多元醇为软段、4,4′-二苯基甲烷二异氰酸酯(MDI)为异氰酸酯组分、乙二醇(EG)和1,4-丁二醇(BDO)为混合扩链剂,采用预聚法制备了聚醚/聚酯基聚氨酯弹性体(PUE).讨论了EG/BDO质量比对PUE微相分离结构、刚性、阻尼性能、热稳定性及力学性能的影响.结果表明,随着EG含量增加,PUE的微相分离程度增加,刚性增加,阻尼性能提高;引入EG扩链剂后,PUE的热稳定性降低;当EG/BDO质量比为70∶30 时,所得PUE综合力学性能较优.

采用"一步法"复合改性工艺制备大分子偶联剂KH570-g-PLA改性绢云母,以改性前后绢云母的浊度和接触角为参数对绢云母表面改性工艺进行优化,考察了改性剂用量、反应时间和反应温度对绢云母表面改性效果的影响.试验结果表明,KH570-g-PLA改性绢云母的最佳工艺条件为聚乳酸(PLA)用量10％、反应温度110℃、反应时间4 h,此时其浊度为809 NTU,接触角为66°.相比未改性绢云母,浊度提高196％,接触角提高285％.测试分析表明,大分子偶联剂KH570-g-PLA被成功偶联到绢云母表面,KH570-g-PLA改性绢云母的晶体片径变小,团聚现象减弱,分散性和疏水性提高,结晶度降低,耐热温度约为705℃.

采用熔融共混技术制备了聚乳酸(PLA)/聚己二酸对苯二甲酸丁二酯(PBAT)复合材料、PLA/绢云母复合材料以及PLA/PBAT/绢云母三元复合材料,以拉伸强度、弯曲强度、断裂伸长率和冲击强度为参数,探究了PBAT和绢云母的用量对PLA基复合材料力学性能的影响.实验结果表明,PLA/PBAT/绢云母复合材料的最佳质量配比为80/20/40时,其综合力学性能最佳,拉伸强度为36.8 MPa,弯曲强度为62.8 MPa,断裂伸长率为9.6％,冲击强度为6.9 kJ/m2.利用扫描电镜分析、差示扫描量热测试以及自然生物降解测试对PLA基复合材料的结构和性能进行表征.结果表明,PLA/PBAT/绢云母(80/20/40)复合材料的力学性能、结晶性能和降解性能最佳,其结晶度为37.1％,六个月自然降解率可达34.8％.