改性云母的制备及在聚丙烯中的应用

发布时间：2018-06-02 19:12

本文选题：云母 + 聚丙烯　；参考：《河北大学》2017年硕士论文

【摘要】：云母(Mica)具有径厚比高、抗压、抗拉强度大,作为无机填充剂应用在高聚物中,能改善高聚物的机械强度。然而云母的表面极性大,与高聚物的相容性差,易团聚且分散不均匀,因此就需要对云母的表面进行改性,以提高云母与高聚物的相容性。本文主要以KH550/石蜡(KP)和KH550/癸二酸(KS)为复合改性剂,分别采用湿法(W)与干法(D)技术改性云母,然后将改性云母与聚丙烯(PP)共混,探讨了改性云母对PP复合材料力学性能的影响,并用锡酸锌(ZS)包覆云母,得到云母基阻燃剂,以进一步拓展云母的应用范围。具体内容如下:第一部分:采用湿法技术改性云母,制备了W-KP和W-KS两种改性云母,研究了改性剂用量和改性时间对云母的影响,采用SEM、FTIR和接触角仪对改性云母进行表征。研究表明:改性后,云母的亲油性和分散性显著提高,其中W-KP的改善效果最佳。当改性剂用量为7%,改性时间为120 min时,W-KP的沉降值由未改性云母的2 mL提高到9.5 mL,接触角由0°提高到20.1°,吸油值由1.7 mL/g降低到1.05 mL/g。将改性前后的云母与PP共混制得PP复合材料,主要分析了PP复合材料的力学性能。发现与未改性PP/Mica复合材料相比,改性PP/W-KP和PP/W-KS复合材料的力学性能得到有效改善,其中PP/W-KP的改善效果最佳。PP/W-KP的断裂伸长率比PP/Mica提高了23.4%,拉伸强度提高了13.4%,缺口冲击强度提高了12.5%,熔融指数提高到9.9g/10min,且收缩率最小降低到1.23%。第二部分:采用干法技术改性云母,制备了D-KP和D-KS两种改性云母,分析了改性剂用量和研磨时间对云母的影响,通过SEM、FTIR、接触角仪和激光粒度仪对改性云母进行表征。结果表明:改性后,云母的亲油性和分散性得到明显改善,云母的层状结构保持良好,粒径有轻微的变化,其中D-KS的综合改善效果最好。当改性剂用量为7%,研磨时间为15 min时,D-KS的沉降值由未改性云母的2 mL提高到17.5 mL,接触角由0°提高到51.3°,吸油值由1.7 mL/g降低到0.85 mL/g。将改性前后的云母与PP共混制得PP复合材料并分析了其力学性能。发现与未改性PP/Mica复合材料相比,PP/D-KP和PP/D-KS复合材料的力学性能得到明显改善,其中PP/D-KP的改善效果最佳。PP/D-KP的断裂伸长率比PP/Mica提高了14.9%,拉伸强度提高了13.2%,缺口冲击强度提高了27.8%,熔融指数提高到6.6 g/10min,且收缩率最小降低到1.20%。对比两种改性效果可以得知,干法所得改性云母的沉降值、吸油值和力学性能优于湿法,但可能会影响云母的粒径大小,破坏材料的结构,而湿法改性云母的热稳定性好。第三部分:通过共沉淀法制备了锡酸锌包覆云母(ZS/Mica),然后用KP和KS改性表面得到云母基阻燃剂,采用XRD、FTIR和SEM-EDS对产物进行表征,之后将云母基阻燃剂应用在PP中制得PP阻燃材料,通过LOI、UL-94、TG、DTG、Cone研究了PP阻燃材料的阻燃性能、热稳定性能和力学性能。研究表明:ZS可包覆在云母表面上,云母基阻燃剂的加入有助于改善PP阻燃材料的阻燃性能、燃烧性能、热稳定性能和力学性能。当云母基阻燃剂添加量为Sb2O3的50%时,PP阻燃材料的垂直燃烧等级保持不变,氧指数提高到24.3%,且PP阻燃材料的热释放总量、热释放速率、烟释放总量和CO2释放速率均有改善,初始热分解温度、残余质量和Tmax略有增加,Rmax降低。且PP阻燃材料的力学性能也得到明显改善,其中经过KP改性PP阻燃材料的力学性能最佳,其断裂伸长率最大提高到583%,拉伸强度提高到37.2 MPa,缺口冲击强度提高到14.2 kJ/m~2,弯曲强度提高到48.3 MPa。
[Abstract]:Mica (Mica) has high diameter thickness ratio, high compressive strength and tensile strength. As an inorganic filler used in polymer, it can improve the mechanical strength of polymer. However, the surface of mica has large surface polarity and poor compatibility with polymers. It is easy to be reunited and disperse unevenly. Therefore, the surface of mica needs to be modified to improve the phase of mica and polymer. In this paper, KH550/ paraffin (KP) and KH550/ sebacic acid (KS) were used as compound modifiers. Wet method (W) and dry method (D) were used to modify mica. Then the modified mica was blended with polypropylene (PP), and the effect of modified mica on the mechanical properties of PP composite was investigated. The mica was coated with zinc stannate (ZS), and the mica flame retardant was obtained. The application scope of mica is expanded step by step. The specific contents are as follows: in the first part, two kinds of modified mica, W-KP and W-KS are prepared by wet technique, and the effect of modifier dosage and modification time on mica is studied. SEM, FTIR and contact angle meter are used to characterize the modified mica. When the dosage of the modifier is 7% and the modification time is 120 min, the settlement value of W-KP is increased from 2 mL to 9.5 mL, the contact angle is increased from 0 degrees to 20.1 degrees, the oil absorption value is reduced from 1.7 mL/g to 1.05 mL/g., and the mixture of mica and PP before and after modification is analyzed, the main analysis is the main analysis. It is found that the mechanical properties of the modified PP/W-KP and PP/W-KS composites are improved effectively compared with the unmodified PP/Mica composites. The best improvement effect of PP/W-KP is 23.4%, the tensile strength is increased by 23.4%, the tensile strength is increased by 13.4%, the impact strength of the notch is increased by 12.5%, and the melting finger is improved. The number was increased to 9.9g/10min, and the minimum shrinkage rate was reduced to 1.23%. second. Two modified mica was prepared by dry technique, D-KP and D-KS were prepared. The effect of the modifier dosage and grinding time on mica was analyzed. The modified mica was characterized by SEM, FTIR, contact angle meter and laser particle size analyzer. The results showed that after modification, mica was modified. The hydrophobicity and dispersity of the mica have been improved obviously. The layer structure of mica is good and the particle size has a slight change. The comprehensive improvement effect of D-KS is the best. When the dosage of the modifier is 7% and the grinding time is 15 min, the settlement value of the D-KS is raised from 2 mL to 17.5 mL by the unmodified mica, the contact angle is increased from 0 to 51.3, and the oil absorption value is 1.7 mL/g. It is reduced to 0.85 mL/g. to blend the mica and PP before and after the modification to obtain the PP composite and analyze its mechanical properties. It is found that the mechanical properties of PP/D-KP and PP/D-KS composites are obviously improved compared with the unmodified PP/Mica composites, and the best improvement effect of PP/D-KP is 14.9% higher than that of PP/Mica, which is better than that of PP/Mica. The tensile strength increased by 13.2%, the notch impact strength increased by 27.8%, the melting index increased to 6.6 g/10min, and the minimum shrinkage rate was reduced to the 1.20%. contrast effect. It was found that the sedimentation value, the oil absorption value and the mechanical properties of the modified mica obtained by dry method are better than the wet method, but it may affect the size of the mica and destroy the structure of the material. The thermal stability of wet modified mica is good. Third part: Zinc Stannate Coated mica (ZS/Mica) was prepared by coprecipitation method. Then the mica based flame retardant was obtained by KP and KS modified surface. XRD, FTIR and SEM-EDS were used to characterize the products. Then the mica based flame retardant was used in PP to produce PP flame retardant, and it was studied through LOI, UL-94, TG, DTG, and DTG. The flame retardancy, thermal stability and mechanical properties of the PP flame retardant materials are investigated. The study shows that ZS can be coated on the mica surface, and the addition of mica based flame retardant helps to improve the flame retardancy, combustion, thermal stability and mechanical properties of the PP flame retardant. When the addition of mica based flame retardant is 50% of Sb2O3, the vertical of PP flame retardant material The oxygen index increased to 24.3%, and the total amount of heat release, the heat release rate, the total amount of smoke release and the release rate of CO2 were improved, the initial thermal decomposition temperature, the residual mass and the Tmax increased slightly, and the Rmax decreased, and the mechanical energy of the PP flame retardant material was also improved obviously, in which the KP modified PP flame retardant material was improved. The mechanical properties of the material are the best, the maximum elongation at break increases to 583%, the tensile strength increases to 37.2 MPa, the notch impact strength increases to 14.2 kJ/m~2, and the bending strength increases to 48.3 MPa..
【学位授予单位】：河北大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TQ325.14;TB332

【参考文献】