三元氯醋树脂/环氧基导电油墨的制备及性能

为提高环氧导电油墨的柔韧性，采用三元氯醋树脂（E15/45M）对环氧树脂E51增韧改性，并以2-乙基-4-甲基咪唑（2E4MI）为固化剂，银包铜粉为导电填料，制备柔性导电油墨。结果表明:导电油墨的体积电阻率随导电填料的用量增加而降低。随2E4MI用量的增加，导电油墨的体积电阻率呈现先降低后增加的趋势，2E4MI与E51的最佳质量比为1∶5。进一步探讨发现导电油墨的最佳固化温度和时间分别为105 ℃和2.5 h。E15/45M不仅可以提高导电油墨的柔韧性，还可以有效降低体积电阻率。随着E15/45M用量增加，E15/45M/E51-2E4MI胶膜的玻璃化转变温度从91.5 ℃降低至58.0 ℃，导电油墨的体积电阻率从27.5×10-4 Ω·cm降低至9.50×10-4 Ω·cm。E51-2E4MI与E15/45M的质量比为50∶50，导电填料用量为70wt%时，导电油墨体积电阻率达到9.57×10-4 Ω·cm，附着力等级为0，涂层反复折叠20次后电阻变化率小于80%。因此采用E15/45M增韧环氧树脂既可以提高导电油墨的柔韧性又可以改善其导电性。 

Preparation and properties of vinylchoride-vinylacetate-dicarboxylic acid terpolymer/epoxy based conductive ink

With the aim of enhancing the toughness of epoxy based conductive ink, we adopted a vinylchoride-vinylacetate-dicarboxylic acid terpolymer (E15/45M) to toughen epoxy resin E51. Flexible conductive ink was prepared with 2-ethyl-4-methylimidazole (2E4MI) as curing agent and Cu@Ag powder as conductive filler. The results indicate that the volume resistivity of conductive ink decreases with the conductive filler content increasing. It also finds that the volume resistivity of conductive ink decreases firstly and then increases, as the content of 2E4MI increases. The optimal mass ratio of 2E4MI to E51 is 1:5, and with further investigation, the best curing temperature and time of conductive ink are 105 ℃ and 2.5 h, respectively. E15/45M can not only enhance the flexibility of conductive ink, but also decreases the volume resistivity. With increasing the content of E15/45M, the glass transition temperature of E15/45M/E51-2E4MI glue film decreases from 91.5 ℃ to 58.0 ℃, and the volume resistivity of conductive ink decreases from 27.5×10^-4 Ω·cm to 9.50×10^-4 Ω·cm. When mass ratio of E51-2E4MI to E15/45M is 50:50, the volume resistivity of the conductive ink with conductive filler content of 70wt% reaches 9.57×10^-4 Ω·cm, the adhesion grade is zero, and the resistance variation is less than 80% after folding repeatedly for 20 cycles. Therefore, toughening epoxy resin with E15/45M can improve both the flexibility and the conductivity of conductive ink.