When it is raining, all we need is water repellent clothing. It would be helpful to wear a hydrophobic clothing to avoid getting drenched.
But did you know water repellent clothes are made with synthetic materials usually vinyl or polyester? These materials are not degradable. They might disintegrate but do not degrade. Polyester clothing might be cheap and best but are not so for the environment.
Many fashion based industries are spending a lot on R&D to find alternative sustainable materials for water repellent clothing. Conventionally used water-repellent coatings still remain in the environment. They are likely to be phased out due to safety issues. This has opened the opportunity for researchers to find an eco-friendly water repellent coating for natural fabrics.
An additional problem with the existing coatings is that they are liquid based. The fabric must be dipped in the liquid to get coated. Dipping results in clogging of the pores in the fabric. The pores need to be opened so that the fabric can be good. So, an extra step is involved to blow open the pores. This adds to cost of manufacturing.
A New Non-toxic Waterproof Coating
A team of MIT researchers has come up with a safe coating for fabrics. The coating adds a water-repellence property to natural fabrics such as cotton and silk. Compared to conventional coatings this is more effective.
According to previous studies, research has shown that polymers with fewer than eight per-fluorinated carbon groups do not persist long and are safe. So, the team worked on short-chain polymers for the hydrophobic coating. Chemical processing of the polymer and different coating process has resulted in good coatings. The coating process used was initiated by chemical vapour deposition. This technique helped in overcoming the problem of using liquid coatings.
The results found by the team are described in a paper published in the journal Advanced Functional Materials.
The researchers say that the coating can be applied on different fabric surfaces. The coated fabrics have passed a number of lab tests, including a standard rain test used by industry.
The coated materials have been through various liquid tests like coffee, ketchup, sodium hydroxide, and various acids and bases. The coating repelled all the liquids. Repeated washing of the coated fabric resulted in no degradation of the fabric. Eventually, the fabric might get damaged but not the coating.
Currently, the team of MIT researchers is planning to optimize the chemical formula for the coating. The patent-pending technology may soon find a market in the fashion industry.