What are the applications of fiberglass in the papermaking industry?

Fiberglass is a new type of inorganic non-metallic material. It is produced from natural ores such as kaolin, pyrophyllite, quartz sand and limestone. Following specific formulas, the materials undergo multiple processes including high-temperature melting, wire drawing and twisting. The diameter of a single filament ranges from several micrometers to over twenty micrometers, equivalent to 1/20 to 1/5 of a human hair. Each strand of original fiber consists of hundreds or even thousands of single filaments.

 

Fiberglass features outstanding properties such as high temperature resistance, excellent corrosion resistance, low moisture absorption and good electrical insulation. It is widely used as reinforcement materials, electrical insulation materials, thermal insulation materials and circuit substrates in composite materials. There are various classification methods for fiberglass, which are generally based on glass composition, single filament diameter, fiber appearance and fiber characteristics.

 

As a kind of industrial paper, fiberglass paper is commonly used for filtration, sound absorption, thermal insulation and electrical insulation. It is made of ultra-fine fiberglass, featuring flame resistance, chemical resistance and superior dimensional stability.

 

This paper can be manufactured on Fourdrinier or cylinder paper machines in two ways: one is using 100% fiberglass (filament diameter below 0.3~0.5μm) with light beating and adhesive addition; the other is blending fiberglass with partial chemical wood pulp. Silica gel or colloidal alumina can also be added to enhance paper strength. Its production process is simpler than conventional papermaking. Fiberglass only needs to be dispersed instead of beaten, and no pressing is required during paper forming.

 

Battery separators are key components of storage batteries. For lead-acid batteries, separators are required to have low electrical resistance, strong acid and oxidation resistance, high porosity with small uniform pores, homogeneous structure and good elasticity. They enable free ion transmission while preventing short circuits between electrode plates.

 

Traditional rubber separators for lead-acid batteries can meet basic performance requirements, yet they have long production cycles and high costs. Their service life fails to match other battery components, as one set of rubber separators can be reused for 2 to 3 batteries, resulting in waste for manufacturers.

 

Fiber composite separators boast abundant raw material sources, low costs, and support the thinning of battery electrode plates. They have been widely adopted overseas to replace rubber separators. A fiber composite separator is composed of a fiber separator and a fiberglass mat bonded with adhesives. The fiberglass mat protects the fiber separator from oxidative corrosion by positive electrodes and prevents short circuits caused by falling active substances on electrode plates.

 

Conventional insulation paper made from plant fibers cannot meet industrial high-temperature service requirements. Therefore, high-performance insulation paper and paperboards are produced by wet forming, blending chemical fibers with excellent insulating properties (such as polyester fiber and polysulfone fiber) and a small proportion of fiberglass. Electrical insulation