摘 要

高分子导电复合材料目前在工业生产和生活中的许多领域都具有广泛的应用前景。但是绝大多数聚合物基导电复合材料的电学性能不稳定。这些缺点制约了材料进一步的推广和应用，限制了材料的应用范围。如何进一步提高导电性能并改善材料电阻率的温度稳定性已成为聚合物基导电复合材料的重要研究方向。

本文利用短切镀镍碳纤维、短切碳纤维、短切玻璃纤维三元混杂纤维增强热固性树脂，制得具有良好导电性的1-1-1-3型导电复合材料。以该1-1-1-3型导电复合材料为研究对象，研究了在不同因素影响条件下，1-1-1-3型导电复合材料的电阻率的温敏特性。本论文采用控制变量法，分别研究了碳纤维含量、镀镍碳纤维长度、树脂基体种类不同的条件下，1-1-1-3型导电复合材料的温敏特性，并做了详细的实验分析。

研究结果表明：

（1）以乙烯基酯树脂为基体，研究了碳纤维含量对导电复合材料温敏特性的影响。从常温升至75℃过程中，碳纤维含量为3%的导电复合材料电阻率变化最小，变化百分比为7%。在60℃下放置5小时时，碳纤维含量为12%的导电复合材料电阻率变化最小，变化百分比为2.4%。可以推测碳纤维用量增加，导电复合材料电阻率的温度稳定性增加。本文中碳纤维用量增加，导电复合材料温敏性规律较差。可能是由于制样效果不好，影响了它的温敏特性，以及数据测试时存在较大误差。

（2）以乙烯基酯树脂为基体，研究了镀镍碳纤维长度对导电复合材料温敏特性的影响。当镀镍碳纤维的长度为10mm时，电阻率温度稳定性最好。从常温升至75℃过程中电阻率变化百分比最大为8.9%。在60℃下放置5小时的电阻率变化值极小，几乎可以忽略。故镀镍碳纤维的长度越长，则导电复合材料的电阻率的温度稳定性越好。

（3）从常温升高至75℃时，环氧树脂为基体的导电复合材料电阻稳定性最好，变化率为1.2%；从75℃升温至150℃，氰酸酯树脂为基体的导电复合材料电阻稳定性最好，变化率为13%。在60℃下放置5小时条件下，氰酸酯树脂为基体的导电复合材料电阻稳定性最好，电阻率变化百分比为1.2%。树脂基体的膨胀性越低，耐热性越好，则导电复合材料的电阻率温度稳定性越好。

关键词：导电复合材料；电阻率；温敏特性

Abstract

Polymeric conductive composites are widely used in many fields of industrial production and life. But the vast majority of polymer-based conductive composites are not stable in electrical properties. These shortcomings restrict the further promotion and application of materials, limiting the scope of application of materials. How to further improve the conductivity and improve the temperature stability of the material resistivity has become an important research direction of polymer-based conductive composites.

In this paper, 1-1-1-3 conductive composites with good conductivity were prepared by using chopped nickel-plated carbon fiber, chopped carbon fiber and chopped glass fiber ternary mixed fiber reinforced thermosetting resin. The thermo - sensitive properties of the resistivity of 1-1-1-3 type conductive composites under different influence factors were studied by using the 1-1-1-3 conductive composites. In this paper, the temperature control properties of 1-1-1-3 conductive composites under different conditions of carbon fiber content, nickel carbon fiber length and resin matrix were studied by using the control variable method, and detailed experimental analysis was carried out.

Research indicates:

(1) The effect of carbon fiber content on the thermo-sensitive properties of conductive composites was studied based on vinyl ester resin. From the normal temperature to 75 ℃, the carbon fiber content of 3% of the conductive composite material resistivity change the smallest.The change percentage is 7%. At 50 ℃ for 5 hours, the resistivity change of the conductive composites with carbon fiber content of 12% was the smallest, with the change percentage of 2.4%. It is speculated that the amount of carbon fiber increases and the temperature stability of the resistivity of the conductive composite increases. In this paper, the amount of carbon fiber increased, the temperature of the conductive composite material is poor. May be due to the sample preparation effect is not good, affecting its temperature-sensitive features, and the data testing has some error.

(2) The effect of nickel-coated carbon fiber length on the temperature-sensitive properties of conductive composites was studied based on vinyl ester resin. When the length of the nickel-plated carbon fiber is 10 mm, the resistivity temperature stability is the best. The maximum percentage change in resistivity during the rise from room temperature to 75 ℃ is 8.9%. The change in resistivity for 5 hours at 60 ℃ is extremely small and can be ignored. The longer the length of the nickel-plated carbon fiber is, the conductive composite has better resistivity stability of the temperature.

(3) From the normal temperature rise to 75 ℃, the epoxy resin as the base of the conductive composite material resistance stability is best, the change rate of 1.2%; from 75 ℃ to 150 ℃, cyanate resin as the base of the conductive composite Material resistance stability of the best, the rate of change of 13%. Under the condition of 60 ℃ for 5 hours, the resistivity stability of the conductive composite material with cyanate ester resin is the best, and the resistivity change percentage is 1.2%. When the resin matrix has lower swelling property, it has better heat resistance, as a result,the conductive composite has better resistivity stability of the temperature.

Key words: conductive composites; resistivity; thermo-sensitive properties

目 录

第1章 绪论 1

1.1高分子导电复合材料概述 1

1.1.1高分子导电复合材料的概念 1

1.1.2高分子导电复合材料的组成 1

1.1.3 高分子导电复合材料导电机理 2

1.2导电高分子复合材料温敏特性研究现状 3

1.3论文研究的目的 4

1.4论文研究的内容 4

第2章 实验原料与设备 6

2.1实验原材料 6

2.2实验设备 6

2.3试样制备工艺及流程 7

2.3.1 电极的制备 7

2.3.2短切镀镍碳纤维/短切碳纤维/短切玻璃纤维/乙烯基酯树脂导电复合材料的制备 7

2.3.3短切镀镍碳纤维/短切碳纤维/短切玻璃纤维/环氧树脂导电复合材料的制备 8

2.3.4短切镀镍碳纤维/短切碳纤维/短切玻璃纤维/氰酸酯树脂导电复合材料的制备 9

2.4 测试方法 9

第3章 1-1-1-3型导电复合材料温敏特性研究 11

3.1碳纤维含量对1-1-1-3型导电复合材料温敏特性的影响 11

3.2镀镍碳纤维长度对1-1-1-3型导电复合材料温敏特性的影响 13

3.3树脂基体种类对1-1-1-3型导电复合材料温敏特性的影响 15

3.4本章小结 17

第4章 结论与展望 18

4.1 结论 18

4.2 研究展望 18

参考文献 20

致谢 21

第1章 绪论

1.1高分子导电复合材料概述

1.1.1高分子导电复合材料的概念

高分子导电复合材料是指以高分子材料作为基体材料,加入各种类型的导电填充材料后，使用不同的复合方式进行处理，从而得到的具有导电特性的多相复合体系^[1]。高分子导电复合材料还具有可设计性的特点。它可以根据设计者的需求，在以较低的成本的条件下，调节材料的电学以及力学性能。所以导电高分子复合材料目前得到了十分广泛的应用。

1.1.2高分子导电复合材料的组成

高分子导电复合材料由多种组分复合而成。其中构成高分子导电复合材料的最重要的部分是高分子基体材料和导电填充材料。

（1）高分子基体材料

高分子基体材料在导电复合材料中发挥着不可或缺的作用。其中最主要的作用有两个方面：①传递基体材料的物理和化学性质从而对导电材料的性质产生影响；②对导电填充材料起固定作用^[2]。导电复合材料的基体材料种类选择十分广泛，目前常见高分子材料绝大多数都可以作为导电复合材料的基体材料使用。设计高分子导电复合材料过程中，在选择基体材料时，主要需要考虑的方面是高分子基体与填充材料之间的相容性以及所要设计的导电复合材料的使用特性^[3]。除此之外,影响其导电性能的因素还有基体材料的一些其他性质，比如聚合度、交联度、结晶度等化学性质^[4]。一般说来，高分子基体材料结晶度越高，导电复合材料的电导率越高；高分子基体材料交联度越高，则导电复合材料的导电稳定性越好。

（2）导电填充材料