Fiberglass Cloth Cleaning Before Impregnation

As a professional manufacturer of PTFE high-temperature fabrics, Jiangsu Aokai New Materials explains how to conduct effective cleaning and dust removal for fiberglass cloth before it enters the impregnation tank.

The cleaning of fiberglass cloth prior to impregnation is a critical step that determines the performance of subsequent composite materials. It serves two core purposes: first, to remove physical impurities such as dust and fiber lint generated during production; second, to thoroughly eliminate the sizing agent coated on fiberglass during wire drawing and weaving, so as to ensure full resin impregnation and firm bonding.

1. Physical Dust Removal: Eliminate Surface Impurities

This is the primary cleaning procedure, targeting loose particles attached during storage and transportation. Modern production processes adopt multiple high-efficiency solutions:

· Brush Roller & Suction CleaningA combined cleaning method. Two sets of high-speed rotating brush rollers thoroughly sweep the cloth surface, while high-power fans blow up dust and suck it into a dust collection device. It delivers excellent results for stubborn adhered contaminants.

· Platform Vibration Beating CleaningMechanical devices perform continuous high-frequency beating on the fabric, shaking off dust from fiber bundles through vibration. It is especially effective for removing fine particles trapped deep in the fabric texture.

· Electrostatic CleaningIn partial production lines, adhesive rollers are used to trap surface dust, followed by high-voltage electrostatic dust absorption for self-cleaning. This non-contact method minimizes damage to high-strength fibers.

2. Sizing Agent Removal: Lay a Foundation for Composite Performance

After physical dedusting, the residual sizing agent that weakens the bonding between fiberglass and resin must be removed. Different desizing processes are adopted according to various sizing agent types:

(1) Removal of starch-based sizing agents

Bio-enzymatic treatment is applicable: clean the fabric in amylase solution at 30～100 ℃ to decompose starch gently via enzymatic hydrolysis with minimal fiber damage.Chemical cleaning is also optional: perform ultrasonic cleaning with absolute ethanol, followed by further ultrasonic rinsing with clean water and solubilizers at 80–90 ℃ to eliminate residual contaminants.

(2) Removal of paraffin-based sizing agents

High-temperature thermal cleaning is the mainstream solution: place the fiberglass cloth in a high-temperature environment of 400–430 ℃ to burn and decompose paraffin sizing agents, reducing organic residue to below 0.04%.Alternatively, repeatedly clean the cloth in hot water or specially formulated hot solution at 65～80 ℃.

(3) Universal high-efficiency cleaning method

Ultrasonic cleaning generates micro bubbles through high-frequency vibration. The shock waves produced by bubble rupture efficiently remove sizing agents and stains without dead corners.In industrial production, a comprehensive dewaxing formula mixed with clean water, solubilizers and penetrants is widely applied.

3. Post-Cleaning: Drying and Surface Modification

Wet fiberglass cloth after cleaning must be fully dried. Hot air drying at around 110 ℃ or multi-stage air drying is commonly used to ensure complete dryness and dimensional stability, preparing the fabric for subsequent impregnation.

For high-performance applications, pre-treatment with low-concentration silane coupling agent is added. Acting like double-sided tape, the coupling agent connects fiberglass on one side and impregnated resin on the other, greatly enhancing the interfacial bonding strength and overall performance of composite materials.

At present, the industry widely integrates multiple physical dedusting technologies. Patented combined equipment completes brushing, suction and beating procedures in one station to boost production efficiency.

In summary, the standard high-efficiency cleaning process is summarized as follows: complete physical dust removal and desizing first, conduct thorough drying, and apply coupling agent pre-treatment if required. Finally, the clean and dry fiberglass cloth is delivered to the impregnation tank.

This technical article is provided by Jiangsu Aokai New Materials Technology Co., Ltd.

If you need detailed parameters, application scenarios and customized solutions for our full product range, including PTFE high-temperature fabric, PTFE high-temperature tape, PTFE high-temperature mesh belt, seamless bonding machine belt, single-sided PTFE coated cloth, high-temperature resistant conveyor belt and heat-resistant fiberglass cloth, please contact us:

· Mr. Guo: +86 18944819998

· Mr. Liu: +86 13705266308

We always adhere to the business philosophy of professionalism and integrity, and strive to provide you with one-stop customized solutions and thoughtful after-sales service.