Preparation method of polyester chip for solar battery back film

Abstract

The present invention discloses a preparation method of a polyester chip for a solar battery back film. A polyester chip semi-finished product with intrinsic viscosity of 0.60-0.64 dl / g and terminal carboxyl group content of 12-18 mol / t is subjected to solid phase polycondensation to obtain the polyester chip for solar battery back film with intrinsic viscosity of 0.75-0.80 dl / g and terminal carboxyl group content of 5-10 mol / t. The preparation method has simple reaction conditions and low production costs; the obtained polyester chip can be separately produced into polyester film suitable for solar battery back without the addition of an anti-hydrolysis agent or an ultraviolet absorber, wherein the polyester film has good water vapor barrier property, resistance to wet heat aging and resistance to light aging. The method is not only friendly to the environment and human, but also avoids the problems of uneven dispersion and inconsistency of product performance of blend film production.

Description

technical field [0001] The invention relates to a method for preparing a polyester chip, in particular to a method for preparing a polyester chip for a solar battery backplane film. Background technique [0002] Solar cells are mainly prepared by laminating toughened glass, EVA glue, battery sheets, and back sheets. Solar cells are easily corroded by water vapor, acid gas, etc., causing their performance to decline. The backsheet has reliable insulation, water resistance, and aging resistance, and supports and protects the solar cells to ensure the long-term service life and stability of the solar cells. [0003] Existing solar cell backsheet films mainly include glue-coated composite backsheet films and coated backsheet films. The common backsheet structures mainly include TPT, TPE, etc., where T stands for fluorine-containing film, E stands for EVA film, and P stands for PET film. [0004] PET film usually has good mechanical properties, optical properties, and chemical...

AI Technical Summary

Problems solved by technology

The deficiency of this document is that the addition of anti-hydrolysis agents and ultraviolet absorbers not only has problems such as environmental pollution and harm to the human body, but also reduces the optical and mechanical properties of the material to a certain extent.

The deficiency of this document is that the price of modified polyester resin chip is relatively high, resulting in high production cost

[0007] In addition, there is a common problem in the above two documents: two or more polyester chips need to be blended to prepare polyester film, which is very easy to produce uneven dispersion, resulting in performance differences between products

The deficiencies of this document are: (1) The conditions of the solid-state polymerization reaction are relatively harsh, and the content of ethylene glycol and water needs to be strictly controlled, and the polymerization time is as long as about 25 hours; The content is more than 20mol / t, so that the terminal carboxyl group content of the polyester resin after solid-state polymerization is mostly more than 10mol / t, which affects the moisture and heat aging resistance and light aging resistance of the prepared polyester film.