【摘要】：玄武巖纖維增強(qiáng)熱塑性復(fù)合材料具有高強(qiáng)度、高模量、耐高溫、可循環(huán)利用、環(huán)境適應(yīng)性強(qiáng)等特點(diǎn),廣泛應(yīng)用于汽車、航天、船舶等工業(yè)領(lǐng)域,可以達(dá)到節(jié)能降耗、綠色環(huán)保的目的。研究玄武巖纖維增強(qiáng)熱塑性復(fù)合材料具有一定的現(xiàn)實(shí)意義。本文采用熔融浸漬拉擠工藝制備了長玄武巖纖維增強(qiáng)尼龍6(LBF/PA6)復(fù)合材料,通過研究不同浸漬模具、不同張緊力、不同模具溫度下的浸漬效果,確定了制備LBF/PA6復(fù)合材料的最佳工藝參數(shù),并對所制備的復(fù)合材料的力學(xué)性能、非等溫結(jié)晶及熔融行為、晶體結(jié)構(gòu)、結(jié)晶形態(tài)及界面形貌進(jìn)行了研究。針對復(fù)合材料界面結(jié)合較弱的缺點(diǎn),采用了兩種方法對復(fù)合材料進(jìn)行了界面改性,進(jìn)一步研究了鹽酸、硅烷偶聯(lián)劑對復(fù)合材料界面的改進(jìn)效果。對LBF/PA6復(fù)合材料的制備工藝參數(shù)研究表明,輥系組合浸漬模具制備的復(fù)合材料中的纖維的分散性最好,浸漬效果最佳。熔融浸漬過程中張緊力對復(fù)合材料的粒料浸漬效果有較大的影響,當(dāng)張緊力為19N時(shí),所得粒料的浸漬效果最佳。模具溫度也是影響浸漬效果的重要因素,當(dāng)模具溫度為255℃時(shí),所得復(fù)合材料粒料的浸漬效果最佳。長玄武巖纖維對PA6有明顯的增強(qiáng)效果,當(dāng)LBF/PA6復(fù)合材料中玄武巖纖維含量為40%時(shí),復(fù)合材料的拉伸、彎曲和沖擊強(qiáng)度分別提升了179.69%、178.42%和306.36%。動(dòng)態(tài)力學(xué)分析(DMA)的結(jié)果表明,長玄武巖纖維的加入能提高LBF/PA6復(fù)合材料的儲(chǔ)能模量和玻璃化轉(zhuǎn)變溫度。在高溫下玄武巖纖維對復(fù)合材料儲(chǔ)能模量的提高要明顯高于低溫下,且玄武巖纖維的加入能明顯提高復(fù)合材料的熱模量保留率,這預(yù)示著復(fù)合材料負(fù)荷變形溫度的提高。長玄武巖纖維對PA6具有異相成核作用,使復(fù)合材料的結(jié)晶速度明顯變快,同時(shí)又有阻礙鏈段運(yùn)動(dòng)的作用。當(dāng)纖維含量較低時(shí),成核作用占主導(dǎo)地位,使復(fù)合材料的T0和Tp升高;當(dāng)纖維含量較高時(shí),阻礙作用占主導(dǎo)地位,使復(fù)合材料的T0和Tp下降。非等溫結(jié)晶后的熔融曲線和廣角X射線衍射(WAXD)譜圖表明,單純PA6中只有α晶形成,而加入玄武巖纖維使PA6形成了α晶和γ晶兩種不同的晶型,偏光顯微鏡(POM)結(jié)果表明玄武巖纖維使PA6基體的球晶尺寸減小,且沿著纖維表面生成了一層微小的柱狀晶體,但這種柱狀晶體的形成很不均勻。臨界纖維長度的理論計(jì)算和復(fù)合材料的掃描電鏡(SEM)照片表明,纖維與基體的界面黏結(jié)力較差,為此對復(fù)合材料的界面改善進(jìn)行了探討。鹽酸和偶聯(lián)劑處理纖維均能有效的改善LBF/PA6復(fù)合材料的界面。當(dāng)鹽酸濃度為10%,處理時(shí)間為1h時(shí),拉伸強(qiáng)度和沖擊強(qiáng)度分別比未處理提高了8.94%和23.02%。硅烷偶聯(lián)劑能在纖維與基體間形成化學(xué)鍵,從而大幅度提高了復(fù)合材料的力學(xué)性能,其中KH550對復(fù)合材料的界面改善效果最好,使復(fù)合材料的拉伸強(qiáng)度和沖擊強(qiáng)度分別提高了17.46%和30.52%。
[Abstract]:Basalt fiber reinforced thermoplastic composites have the characteristics of high strength, high modulus, high temperature resistance, recyclability and strong environmental adaptability. Basalt fiber reinforced thermoplastic composites are widely used in automobile, aerospace, shipping and other industrial fields, and can achieve energy saving and consumption reduction. The purpose of green environmental protection. It is of practical significance to study basalt fiber reinforced thermoplastic composites. In this paper, long basalt fiber reinforced nylon 6 (LBF/PA6) composites were prepared by melt impregnation and extrusion process. The impregnation effects of different dipping molds, different tensile forces and different die temperatures were studied. The optimum technological parameters for the preparation of LBF/PA6 composites were determined, and the mechanical properties, non-Isothermal crystallization and melting behavior, crystal structure, crystallization morphology and interface morphology of the composites were studied. In order to solve the problem of weak interfacial bonding of composites, two methods were used to modify the interface of composites, and the improvement effect of hydrochloric acid and Silane coupling agent on the interface of composites was further studied. The preparation process parameters of LBF/PA6 composites were studied. the results showed that the dispersion of the fibers was the best and the impregnation effect was the best among the composites prepared by roller combined dipping mould. The tensile force has a great influence on the impregnation effect of the composites during melt dipping. When the tensile force is 19N, the impregnation effect of the obtained particles is the best. Die temperature is also an important factor affecting the impregnation effect. When the die temperature is 255 鈩，

本文編號：2478258