本文關鍵詞：單聚合物復合材料模內(nèi)自增強成型特性的研究　出處：《大連理工大學》2016年碩士論文　論文類型：學位論文

  更多相關文章： SPC 共注塑 物理可視化技術 型腔壓力 熔體溫度

【摘要】：單聚合物復合材料(Single Polymer Composites,以下簡稱SPC)是基體和增強相采用同種(族)聚合物的復合材料。SPC具有比強度高,不存在界面異性,易于回收等優(yōu)點。傳統(tǒng)制備SPC的熱壓工藝,具有成型過程復雜、效率低和材料選擇面窄的局限性,這成為了SPC應用的瓶頸。本文提出了模內(nèi)自增強復合工藝成型SPC的方法,即利用共注塑工藝制備SPC,通過注塑工藝分別完成SPC基體和增強相的制備,這種方法具有工藝簡單、成型周期短和材料選擇寬泛等優(yōu)點。增強相、基體和界面都影響SPC材料整體的性能,尤其是增強相和界面性能；根據(jù)聚合物材料的性質(zhì),不同注塑工藝參數(shù)得到的制品性能也不同；本文利用物理可視化和傳感器測量等手段,研究了成型工藝參數(shù)對SPC增強相制備過程的影響。以PP作為成型材料,改變增強相的成型條件制備對應的SPC力學性能試樣,取單次注塑的未增強試樣作為對照,測量各組試樣的拉伸強度。當塑化溫度為230℃,注射速度為6.11cm3/s時,SPC的拉伸強度最大,比對照組高23.79%。利用物理可視化技術獲得不同條件下熔體前沿的流動速度曲線；相對于熔體在金屬溝槽的填充,SPC基體的存在使得熔體的流動速度更大,共注塑成型工藝更有利于發(fā)揮增強相聚合物的自增強特性；不同增強相尺寸的SPC填充結果表明：尺寸2mm,1.5mm和1mm的增強相均能順利充滿型腔,而尺寸0.5mmm的增強相熔體充模時發(fā)生短射現(xiàn)象；相同成型條件,小尺寸增強相的前期流動速度更大,而大尺寸增強相熔體中后期流動速度更大。分別在型腔的近澆口,型腔中部和型腔末端三個位置,利用傳感器測量尺寸2mm的SPC增強相成型時的型腔壓力和熔體溫度。熔體實際流動速度是型腔壓力的主要影響因素。對某一成型過程,熔體與接觸壁面的熱傳導以及熔體流動過程中的粘性耗散作用是影響熔體溫度的主要因素。利用MoldFlow對本文中所有的實驗過程進行了模擬,包括不同增強相尺寸SPC的填充過程和PP熔體在金屬溝槽中的填充過程,并分別從熔體流動前沿溫度和重新熔化區(qū)域兩個方面進行了對比分析。塑化溫度越高,注射速度越大,對應的熔體流動前沿溫度越高,基體界面的重新熔融區(qū)域越大；對比力學性能試驗結果,說明界面強度是除增強相強度之外,影響SPC拉伸強度的又一主要因素；其他模擬分析結果與前期的實驗結果一致。
[Abstract]:Single Polymer Composites. SPCs are composites with the same group of polymers used in matrix and reinforced phase. SPCs have the advantages of high specific strength, no interfacial heterogeneity and easy recovery. Because of the limitation of complex molding process, low efficiency and narrow choice of materials, this has become the bottleneck of SPC application. In this paper, a method of forming SPC by in-mold self-reinforcing composite process is proposed. This method has the advantages of simple process, short molding period and wide selection of materials, and can be used to prepare SPC matrix and reinforcement phase respectively by injection molding process, which has the advantages of simple process, short molding period and wide selection of materials, etc. The method has the advantages of simple process, short molding period and wide selection of materials. Both the matrix and the interface affect the overall properties of the SPC material, especially the reinforcing phase and the interfacial properties. According to the properties of polymer materials, the properties of the products obtained by different injection molding parameters are also different. By means of physical visualization and sensor measurement, the influence of molding process parameters on the preparation of SPC reinforced phase was studied. PP was used as the molding material. The mechanical properties of SPC samples were prepared by changing the forming conditions of the reinforcing phase. The tensile strength of each group of specimens was measured when the plasticizing temperature was 230 鈩，

本文編號：1389474