本研究利用過氧化苯甲醯(BPO)/檸檬酸鈉(Na3CA)/乙醯丙酮鈷 (Cobalt(II) acetylacetonate, Co(acac)2)觸媒進行乙酸乙烯酯(Vinyl acetate, VAc)與苯乙烯(St)的有機鈷觸媒活性自由基聚合(Cobalt-Mediated Radical Polymerization, CMRP)反應，聚合程序採一鍋法(One pot synthesis)可成功地聚合出 PDI在 1.3 以下的PVAc高分子鏈段；銜接第二鏈段的St聚合反應受到苯環結構的共軛影響，合成出Poly(VAc-b-PS) 嵌段共聚合物的 PDI 上升至 1.6。此嵌段共聚合物可經鹼液改質為可以有效分散奈米碳管(CNT)的聚(乙烯醇-苯乙烯) (Poly(VA-b-PS))嵌段共聚物雙親性高分子(Amphiphilic Polymer)材料。利用莫爾比 PVA : PS = 1 : 1.5 之嵌段共聚物作為CNT分散劑時，可成功的將CNT分散於N-甲基吡咯烷酮 (N-Methyl-2-pyrrolidone, NMP)溶劑中。另一方面，當添加0.005 wt% CNT於CNT/PVA材料時，CNT/PVA的導電度可達到4.86 x 10-4 Sm-1 (log σ = -3.31)的導電門檻(threshold)。當以Poly(VA-b-St)做為CNT在丙烯酸甲酯-丙烯酸丁酯-甲基丙烯酸縮水甘油酯共聚合物(Poly(MMA-co-BA-co-GMA))材料分散介質時，則只有1/100的添加比例，即可將0.3wt.% CNT均勻分散於Poly(MMA-co-BA-co-GMA)材料中。Poly(VA-b-St)的添加不僅可使Poly(MMA-co-BA-co-GMA)導電值達2.603 x 10-3 Sm-1的高導電值，且因Poly(VA-b-St)中的氫氧基(-OH)可與Poly(MMA-co-BA-co-GMA)中的環氧基進行開環交鏈反應，提升整體的耐溼性能及機械強度。

Poly (VAc-b-St) block copolymers were synthesized using cobalt-mediated radical polymerization (CMRP). A redox system, which consists of benzoyl peroxide (oxidant) and sodium citrate (reductant), was used to initiate CMRP in the presence of cobalt (II) acetylacetonate (Co(acac)2). Poly (VA-b-St), prepared by methanolysis of Poly (VAc-b-PS), were used as dispersants of CNT in NMP solution and successfully dispersed CNT for 20 days.

Carbon nanotubes (CNT)/polymer matrix composite films were made using Poly (VA(13,000)-b-St(46,000)) with PVA/PS molar ratio of 1/1.5 as dispersants. With 0.005 wt.% CNT loadings, the electrical conductivity of CNT/PVA films is 1.077 x 10-3 Sm-1, and the percolation threshold lies below 0.005 wt.%. Furthermore, in the Poly (MMA-co-BA-co-GMA)/Poly (VA-b-St) weight ratio of 100/1, the electrical conductivity of CNT/Poly (MMA-co-BA-co-GMA) film were improved and reached the percolation threshold at 0.3 wt.% CNT loadings. The acrylic materials were more resistant to moisture than the PVA due to the crosslinking reaction between the epoxy group of Poly (MMA-co-BA-co-GMA) and the hydroxyl group of Poly (VA-b-St).

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