With the requirements of the working environment for fabrics and the development of society, waterproofing agent was born, which brings us a lot of convenience and protection. In the pursuit of perfect performance, the transformation from fluorine-free water repellent to superior fluorine-based C8 water repellent, now the performance of C8 water repellent is becoming more and more perfect. But when the performance has just been perfect, it has to change to the fluorine-based short carbon chain C6, which has a slightly poorer waterproof performance. Why is this?

Studies have found that the production of C8 by electrolysis will be accompanied by a by-product called perfluorooctane sulfonic acid (PFOS), and the production of C8 by telomerization will be accompanied by a by-product called perfluorooctanoic acid (PFOA):

The chemical formula of PFOS is CAF180X. Through research, it has been found that PFOS has:

①Persistence-it will not decompose even when boiled in sulfuric acid; there is no degradation when the pH in water at 50°C is from 1.5 to 11.0; the half-life of PFOS is determined to exceed 41 years.

②Bioaccumulation-the accumulation level is higher than that of organochlorine pesticides and dioxins; fish bioconcentration factor: 2796-3100; half discharge time: it takes 8.7 years to enter the body.

③ Toxicity-genetic toxicity, male reproductive toxicity, neurotoxicity, etc.; animal experiments have shown that 2 mg of PFOS per kilogram of animal body weight can cause death.

The chemical formula of PFOA is CF10H. PFOA is also a substance similar to PFOS. Compared with PFOS, PFOA has a shorter half-life and lower toxicity, but it will remain in the human body for as short as four years and can be carcinogenic. Studies have found that it can induce tumors in different parts of the testis, pancreas, and breastfeeding, and cause weight loss in experimental animals.

According to the latest environmental protection requirements of 0EKO-TEX Standard100 on April 1, 2015, the content of PFOA and PFOS in the fluorine-based water repellent must be less than 1ug/m2, while the content of PFOA and PFOS in the C8 water repellent exceeds the standard and does not meet the environmental protection requirements. Prohibited to use. The content of PFOA and PFOS in C6 waterproofing agent cannot be detected, which is lower than the detection limit of 1ug/m, so C6 waterproofing agent is environmentally friendly and meets various international environmental protection requirements.

It can be seen from the above that although the waterproof performance of C8 waterproofing agent is perfect, it will cause great harm to people and pollute the environment. The C6 waterproofing agent does not produce PFOS and PFOA during production, and its performance is close to C8 after several years of careful research and development. Therefore, from the perspective of environmental protection, the change from C8 to C6 is people’s attention to the environment. A manifestation of self-protection.