Unidirectional heat transfer flame retardation PTC macromolecule self-limiting temperature electrothermal film and preparation method thereof

Abstract

The invention discloses a unidirectional heat transfer flame retardation PTC macromolecule self-limiting temperature electrothermal film. The electrothermal film comprises: a reflecting layer, a first insulating layer, a macromolecule PTC conductive woven layer, a second insulating layer and a fire-retardant layer, wherein the reflecting layer, the first insulating layer, the macromolecule PTC conductive woven layer, the second insulating layer and the fire-retardant layer are successively arranged from bottom to top. The macromolecule PTC conductive woven layer comprises: a woven bottom layer, a carbon black filling type polyvinyl PTC conductive fiber and a current-carrying strip. Raw materials of the carbon black filling type polyvinyl PTC conductive fiber comprise: polyethylene, an ethylene-vinyl acetate copolymer, carbon black and the like. A foaming flame retardation insulating layer is arranged under the reflecting layer. The electrothermal film of the invention possesses advantages of unidirectional heat transmission and the flame retardation. Usage performance is stable and a service life is long. In a preparation method of the invention, a three-roller calender is used toperform calendaring and combining, water cooling and rolling the each forming layer so as to obtain the electrothermal film. The method and a technological process are simple. Costs are low and the method is easy to realize.

Description

technical field [0001] The invention belongs to the technical field of electrothermal material preparation, and in particular relates to a unidirectional heat transfer flame-retardant PTC polymer self-limiting temperature electrothermal film and a preparation method thereof. Background technique [0002] Planar electric heating products are mainly composed of semiconductor heating elements, current-carrying bars, and insulating materials. The mainstream product of low-temperature radiant electric heating film is made of parallel conductive ink bus bars and silver powder coating bus bars sandwiched between insulating polyester (PET) films. The electric heating film is connected to the power supply through wires to convert electrical energy into heat energy. The American Calorique electric heating film contains two layers of insulating polyester film, and the middle ink line is conductive ink, with a thickness of about 0.2mm to 0.3mm. Chinese patent application number 9911133...

AI Technical Summary

Problems solved by technology

Due to the difference in thermal expansion coefficient between the conductive film layer and the base material, air bubbles are easily formed between the conductive film layer and the base material after repeated heating-cooling, causing the conductive film layer to fall off; at the same time, repeated heating-cooling causes the conductive film layer to easily produce tiny cracks, making the resistance The value gradually increases during use, and the electric heating power attenuation is more obvious

In addition, the leakage current of the traditional planar heating film is relatively large, and it is difficult to pass through the existing leakage protection device, posing a safety hazard

Images