PTC thermistor base material and preparation method thereof

Abstract

The invention belongs to the field of a high-molecular material, and more specifically relates to a PTC thermistor base material and a preparation method thereof. The PTC thermistor base material comprises the following raw materials in parts by weight: 60-70 parts of HDPE, 15-20 parts of PET, 3-5 parts of EEA, 25-30 parts of silver-plated copper powder, 4-8 parts of carbon fiber, 0.8-1 part of graphene, 5-6 parts of palygorskite powder, 3-5 parts of basalt fiber, 3-4 parts of wollastonite, 2-3 parts of mica powder, 2-3 parts of dicumyl peroxide, 5-8 parts of a nano filling material, 3-5 parts of a coupling agent, 2-3 parts of an anti-oxidant, and 2-4 parts of an organosilicon fire retardant. The preparation method comprises the steps of weighing, premixing and mixing. The PCT thermistor has low room-temperature resistivity, high heat resistance, high stability and high intensity, and excellent comprehensive property.

Description

technical field [0001] The invention belongs to the field of polymer materials, and in particular relates to a PTC thermistor substrate and a preparation method thereof. Background technique [0002] PTC (positive temperature coefficient) is a positive temperature coefficient thermosensitive material, which has the characteristic that the resistivity increases with the increase of temperature. PTC elements can be composed of ceramics or organic polymers doped with conductive particles such as graphite or carbon black. The conductive particles allow the flow of electric current at low temperatures due to their contact with each other, but by heating the polymer matrix expands so that the contact of the particles becomes loose and eventually the current flow is blocked or even no longer possible. Today, PTC thermistors are widely used in heaters. [0003] At present, many PTC thermistors use polymer material HDPE, but its melting point is only about 130°C, which limits the a...

AI Technical Summary

Problems solved by technology

[0003] At present, many PTC thermistors use polymer material HDPE, but its melting point is only about 130°C, which limits the application range of PTC materials.

At the same time, the current organic PTC materials mainly use graphite and carbon black as conductive fillers, which mainly have problems such as wide room temperature resistance distribution, low PTC strength, and low stability.

[0004] Chinese patent CN 104861273 A discloses a "composite material for thermistor and its preparation method and application", which uses HDPE as the main matrix, and uses specific proportions of titanium diboride, carbon fiber and multi-walled carbon nanotubes As a conductive filler, the material has good comprehensive performance in terms of room temperature conductivity, PTC strength and stability, but due to the influence of the melting point of HDPE itself, its application range is limited