玻璃纤维增强PA6的偶联剂种类优选

采用同一处理条件,分别应用KH550、KH560、KH570、KH792、DL602五种不同种类的偶联剂对玻璃纤维进行处理,与PA6共混制备了玻璃纤维增强尼龙6复合材料(PA6/GF)。考察了偶联剂种类对复合材料力学性能的影响。结果表明,硅烷偶联剂可以附着在玻璃纤维表面,偶联剂处理液种类对处理效果有影响。不同型号的硅烷偶联剂处理后的玻璃纤维制备的复合材料的性能不同,在考察的五种偶联剂中,经过KH550处理的复合材料弹性模量和断裂强度最大。硅烷处理液种类对复合材料的冲击强度影响不大。     

偶联剂对玻璃纤维增强环氧复合材料吸湿及力学性能的影响

采用有机硅偶联剂KH550和KH560对玻璃纤维表面预处理或与基体混合,研究了偶联剂对玻璃纤维增强环氧复合材料(GF/E-51)的吸湿及力学性能的影响.结果表明,偶联剂KH550和KH560预处理法使平均吸湿速率分别下降了31.8%和59.4%,但对饱和吸湿量基本没有影响,而与基体混合则使饱和吸湿量分别增加了36.4%和17.1%;通过有机硅偶联剂KH550和KH560处理能显著提高干燥GF/E-51试件的层间剪切强度,而通过与基体混合,添加5%的KH550或KH560,使剪切强度分别提高了38.5%或55.6%;而通过对玻璃纤维表面预处理,KH550和KH560使剪切强度分别提高了16.9%和14.9%.但是,对饱和吸湿的GF/E-51试件,仅KH550对玻璃纤维表面预处理的一种GF/E-51试样的剪切强度提高了10.3%.     

表面处理对铝合金粘接修理性能的影响

GFRP粘接修复损伤铝板,粘接前对损伤铝合金表面采用不同浓度的硅烷偶联剂KH550、KH560进行处理,以未经偶联剂处理的铝板为对照组,通过拉伸试验与湿热试验研究偶联剂处理对修复效果的影响。试验结果表明:两种偶联剂KH550、KH560处理铝合金效果相当,铝板表面经1%~2%浓度的偶联剂溶液处理不仅有较高的初始强度,而且耐湿热性能也得到提高;湿热处理使不同表面处理的修理试样力学性能发生明显下降,同时,湿热环境对铝板-胶层之间粘接界面的渗透破坏要强于其对胶层-GFRP之间的界面破坏,铝板-胶层界面粘接强度的下降是引起试样性能下降的主要原因。     

不同硅烷偶联剂对氧化镁填充导热尼龙6性能的影响

分别用四种不同的硅烷偶联剂处理氧化镁,研究了不同偶联剂表面处理后的氧化镁填充尼龙-6导热复合材料的力学性能、热变形温度和导热性能。结果表明,硅烷偶联剂处理后氧化镁/尼龙6复合材料的强度、刚性和导热性能明显提高,热变形温度则略有上升。四种硅烷偶联剂对氧化镁表面处理效果从好至差依次顺序为KH792KH550KH160KH560。     

竹材表面处理对胶合性能的影响

为提高竹材的胶合性能,用自制的偶联剂对竹材表面进行预处理,测试了处理前后表面接触角的变化,从而计算出竹篾外表面自由能及其分量的变化。将处理的竹篾压制成竹篾层积材,测试了竹篾层积材的物理及力学性能,并与未处理竹篾层积材进行了比较。研究结果表明,经偶联剂处理的竹篾表面自由能提高,压制的竹篾层积材的胶合强度也有明显的提高,还对偶联剂处理前后强度变化的原因进行了探讨。     

表面处理对可生物降解黄麻/PLA复合材料结构和性能的影响

采用注塑成型法制备了生物降解黄麻短纤维增强PLA复合材料,通过力学性能测试及SEM,探讨了碱处理、碱和硅烷偶联剂KH550同时处理对复合材料结构和性能的影响。结果表明:两种处理方法均能够增加黄麻纤维的表面粗糙度,但碱和偶联剂KH550同时处理的效果要优于碱处理,且KH550改善了黄麻短纤维与PLA树脂之间的界面黏结性能提,高了黄麻/PLA复合材料的拉伸强度和弯曲强度。     

硅烷偶联剂对ZnO/PA6复合材料力学性能的影响

以硅烷偶联剂KH550和KH560为改性剂对ZnO粉体进行表面改性,KH550带有氨基团,KH560带有环氧基团,通过HAAKE双螺杆混合机制备ZnO/PA6复合材料。红外光谱证实改性后两种偶联剂均与ZnO表面发生了化学键和;结果表明经偶联剂改性的氧化锌比未改性的氧化锌能更好的提高PA6的拉伸强度,而且在ZnO的添加量为2%～3%时对PA6力学性能的改善达到一个最佳效果。     

二氧化钛粉体的表面改性研究

针对二氧化钛和二氧化硅粉体的表面改性,研究了不同偶联剂种类、偶联剂含量和不同水解环境下粉体的改性效果.实验结果显示,对于不同种类偶联剂KH550、KH560、KH570改性二氧化钛,KH570改性的二氧化钛沉降体积最大,亲油化度也最大,改性效果较好.在中性预水解条件下偶联剂对二氧化钛粉体的改性效果均优于酸性和碱性条件....     

改性小麦秸秆纤维对PBS复合材料性能的影响研究

采用NaOH对小麦秸秆纤维进行处理,在此基础上使用蒸煮助剂Na2S2O4和偶联剂(KH550、KH560)改性秸秆纤维,并将其分别与聚丁二酸丁二醇酯(PBS)共混,制备了秸秆纤维/PBS复合材料.研究了NaOH处理中Na2S2O4的添加以及NaOH处理后KH550、KH560的改性对复合材料性能的影响.采用EDS、WXRD和SEM对改性前后的纤维及复合材料分别进行了分析和观测.研究结果表明:NaOH同3％ Na2S2O4混合处理得到的复合材料的性能最好,KH560较KH550更能有效地改善复合材料的力学性能,当KH560质量分数为2％时,复合材料的力学性能最好.     

碳纤维处理方法对PE-HD／EVA／CF复合材料导电性能的影响

研究了碳纤维（CF）不同的表面处理方法对PE—HD／EVA／CF复合材料导电性能的影响，包括硝酸液相氧化处理和硅烷偶联剂KH560、KH550包覆处理。结果表明，用偶联剂处理的复合体系，其体积电阻率随着CF的用量增加呈下降趋势。KH560包覆处理体系的最低体积电阻率为3．63×10^9Ω·cm，KH550处理体系为7．94×10^9Ω·cm。KH560的偶联处理效果总体较佳，导电渗阈值出现在5份，而且KH560最佳使用量为0．8份。硝酸液相氧化处理效果比偶联剂好，随着氧化时间的延长，复合体系的导电性能随之改善，最佳氧化时间为7h，其导电渗阈值在3．5份左右，体积电阻率从10^13Ω·cm下降到5．75×10^8Ω·cm。     

硅烷偶联剂对玻纤/聚丙烯复合材料的影响

分别选用KH550、KH570两种硅烷偶联剂处理无碱无捻粗纱,采用挤出、注塑成型技术制备玻纤增强聚丙烯复合材料,对复合材料进行了分析和研究。结果表明：硅烷偶联剂具有提高GF/PP复合材料性能的作用。SEM显示KH570处理GF与PP基体之间形成了良好的界面,界面层起到很好的应力传递作用,达到良好的增强效果。     

偶联剂处理对碱式硫酸镁晶须填充UP树脂浇铸体力学性能的影响

利用钛酸酯类偶联剂NDZ101、NDZ401和硅烷类偶联剂KH550、KH570对碱式硫酸镁晶须进行处理,研究了几种偶联剂及其加入比例对晶须填充不饱和聚酯树脂(UP)浇铸体力学性能的影响,并结合应力-应变曲线和SEM的图片,对试验结果进行了讨论。实验结果表明,采用偶联剂处理晶须可改善其填充UP树脂浇注体的拉伸强度、拉伸模量、弯曲模量和冲击强度。其中,采用2%KH570进行处理,拉伸强度改善幅度最高,可提高47.54%;采用3%NDZ101进行处理,拉伸模量和弯曲模量均获得最大幅度的提高,分别为65.99%和69.33%;而采用4%KH550进行处理,却可最大幅度地提高冲击强度,为29.21%。对弯曲强度而言,偶联剂处理总体上对其影响效果不如其它的力学性能那样明显。相对而言,硅烷类偶联剂的效果优于钛酸酯类的偶联剂。加入4%KH570和5%KH550时获得的弯曲强度最大,分别为54.43MPa和53.19MPa,较未处理的浇铸体弯曲强度分别提高了25.10%和22.25%,而采用NDZ101或NDZ401,弯曲强度值却基本上都下降。碱式硫酸镁晶须填充UP树脂浇铸体的断裂属于脆性断裂。     

硅烷偶联剂对纳米Al2O3改性的研究

本工作以改善纳米粒子在环氧树脂基体中的分散性,提高无机粒子与基体的界面结合力为目的,选择了硅烷偶联剂KH550和KH570分别对纳米Al2O3粒予表面进行改性。文章系统研究了各种聚合条件（加料顺序、偶联剂加入量、反应时间）对改性效果的影响。TGA测试表明获得了不同接枝率的改性粒子。改性粒子与环氧树脂反应后进行的TGA测试以及FTIR测试证明了KH550改性的纳米粒子能够与环氧树脂发生反应,而KH570改性的纳米粒子不能发生反应。     

UPR/苎麻布/碱式硫酸镁晶须复合材料Ⅰ——偶联剂处理晶须对复合材料力学性能的影响

选用钛酸酯偶联剂NDZ101、NDZ401和硅烷偶联剂KH550、KH570分别对碱式硫酸镁晶须进行预处理,采用模压工艺制备不饱和聚酯树脂/苎麻布/碱式硫酸镁晶须复合材料,研究了偶联剂加入比例对复合材料力学性能的影响。结果表明:除了KH570外,其他几种偶联剂均可保持或提高复合材料的拉伸强度和冲击强度;除了NDZ101之外,其他几种偶联剂均可提高复合材料的弯曲强度,当选用2%的KH550进行处理时,复合材料的弯曲强度最高,达到104.78 MPa,较未经偶联剂处理的复合材料的弯曲强度(95.18 MPa)提高了10.09%;利用硅烷类偶联剂处理晶须,对复合材料的拉伸模量、弯曲模量的改善效果优于钛酸酯类偶联剂;偶联剂处理不能改变复合材料脆性断裂的性质。     

Aluminum‐borate‐whiskers‐reinforced bismaleimide composites. 1: preparation and properties

Aluminum‐borate‐whiskers‐reinforced bismaleimide (BMI/Al₁₈B₄O₃₃) composites were prepared, and the mechanical and thermal properties were investigated. Results show that the coupling agent used for surface treatment of whiskers has a great effect on the properties of these materials. Composites containing surface‐untreated whiskers, or silane‐compound‐KH 921‐treated whiskers, exhibited initially only a slight increase in the flexural strength when the whiskers weight content increased up to 5 wt%; thereafter, they showed a sharp decrease when the whiskers content was higher than 5 wt%. On the other hand, impact strength tests showed that the addition of the two kinds of whiskers decreased the impact strength of the composites. However, studies of the composite containing borate (BE4)‐treated whiskers showed that its flexural strength greatly increased with increasing whisker content. Moreover, the composite showed initially an increase in impact strength with a whisker content up to 10 wt%, then showing a slight decrease when the whisker content reached 15 wt%. Scanning electron microscopy observations revealed that the two coupling agents (KH 921 and BE4) employed in this work tend to change the fracture features of the composites from brittleness to that of ductile behaviour. Copyright © 2004 Society of Chemical Industry     

Synthesis and properties of novel macromolecular coupling agents prepared by ATRP

Novel block and graft macromolecular coupling agents with well‐defined structures have been synthesized successfully by atom transfer radical polymerization (ATRP). The molecular weights and molecular weight distributions of those functional copolymers can be controlled because of the living/controlled ATRP. The structures and composition of block and graft copolymers with the monomers of butyl acrylate (BA), styrene (St), and 3‐methacryloxyl‐propyltrimethoxyl silicon (KH‐570) have been characterized by mean of ¹H NMR, IR, GPC, and UV. Because the KH‐570 of macromolecular coupling agents owns strong affinity to surface hydroxyl of fillers, inorganic fillers that were treated by the macromolecular coupling agents possess some new properties, for example increasing the effect between matrix and fillers of composites. The mechanical properties and morphology of composites with macromolecular coupling agents have been investigated by the dynamic mechanical spectra and SEM. The results showed that the damping value and compatibility of composites with macromolecular coupling agents were improved greatly when compared with that of composite with small molecular coupling agent. Furthermore with different contents of BA, St, and KH‐570 in the macromolecular coupling agents, the damping value of the composites are different. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 3919–3926, 2006     

Biodegradable Composites: Ramie Fibre Reinforced PLLA-PCL Composite Prepared by in Situ Polymerization Process

Summary  Thermoplastic biodegradable composites based on ramie fibre (RF) and a poly(l-lactic acid)-poly(ε-caprolactone) (PLLA-PCL) matrix was manufactured using the in situ polymerization method. In order to improve the compatibility and strengthen the interface in natural fibre composite materials, the RF was firstly treated by coupling agents. Then the RF reinforced thermoplastic PLLA-PCL composite was prepared by in situ polymerization of PLLA oligomer with NCO-terminated PCL prepolymer. The effect of fibre length and fibre content on tensile strength and impact strength of this natural-fibre-reinforced biodegradable composite (PLLA-PCL/RF) was discussed, including the influence of the use of silane coupling agent (KH550) for improved interfacial adhesion. The results showed that the tensile strength and impact strength of PLLA-PCL/RF were highest when the RF length was 5-6mm, RF content was 45% and with KH550 as surface treatment agent of RF.