本研究利用高溫電紡絲設備製備奈米級聚乙烯纖維，首先以mPE當作研究溶液，探討在不同操作條件下，如：流量 (Q)、溶液黏度、溫度 (Toil)對cone、jet形態、液柱直徑 (dj)及纖維直徑 (df)的影響。實驗發現改變流量與黏度，對液柱、纖維直徑均造成影響，並遵循scaling law的關係式，改變Toil時，纖維直徑隨著溫度上升而有下降的趨勢。

由mPE電紡製程研究中發現8 wt% mPE溶液可得到bead-free纖維，且其電紡製程相當穩定，因此固定此濃度並加入少量超高分子量PE或graphene研究混摻溶液對電紡製程的影響。

純UHMWPE溶液電紡製程相當不穩定，原因是UHMWPE溶液會產生gel而阻塞紡口。本實驗發現加入mPE可以有效降低UHMWPE生成gel的溫度進而穩定的電紡製備纖維。收集mPE/UHMWPE順向纖維並作WAXD、SAXS測試，發現晶體繞射峰不明顯，此乃因結晶性低的mPE在纖維內占絕大部分比例所致。加入graphene的mPE溶液則因graphene具有導電性，可電紡出更細的mPE纖維，但graphene並無法有效的被包覆在纖維內，對於提升纖維導電度的幫助不大。

收集不同電紡條件所得複合纖維並作拉伸測試，由應力-應變圖得知mPE/graphene複合纖維的楊氏模數最大，而純mPE纖維具有最大的韌性。由往復式拉伸測試發現mPE具有類似於橡膠的優異彈性。

High-temperature solution electrospinning was carried out to prepare nano-fibers of metallocene-based polyethylene (mPE). The effect of different processing variables, i.e. flow rate (Q), solution viscosity, circulating oil temperature (Toil) on the Taylor cone, jet length, jet diameter (dj), fiber diameter (df) were investigated. The scaling laws for the mPE solution electrospinning were discovered. The fiber diameter was decreased with increasing Toil.

Based on our findings, a stable process and bead-free fibers could be obtained by electrospinning of 8 wt% mPE solutions. The polymer concentration of 8 wt% mPE solution was fixed to make a further study of electrospinning of polymer blend solutions, i.e. mPE/UHMWPE, mPE/graphene solutions.

Due to the formation of gel, neat UHMWPE solutions would block the spinneret during electrospinning, and the electrospinning of UHMWPE solutions was not a continuous process. The addition of mPE in UHMWPE solution could suppress the gel formation of UHMWPE and a stable electrospinning process of mPE/UHMWPE solution could be attained.

Thinner fibers were produced by electrospinning of mPE/graphene solutions because the solution conductivity was increased by adding graphene. The dispersion of graphene in the mPE fibers was not well so that the conductivity of composite fibers was not obviously improved although 0.5 wt% graphene was added.

The mechanical properties of different composite fibers were measured by an universal tensile testing machine. From the stress-strain curves of fiber mats, mPE/graphene composite fibers had the largest Young’s modulus and neat mPE fibers had the highest toughness. According to the cyclic tensile test, neat mPE fibers had good elasticity which was similar to rubbers.

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