Water-soluble materials are growing in interest for a variety of applications, from single-use detergent pods to plastic bags to flushable wet wipes. These materials are useful for applications in which standard disposal is not an option or where waste accumulation poses a particular problem. Many brands are looking for solutions beyond water-soluble that are bio-based and more readily biodegradable as well. In this blog, we dive into the existing opportunities for water-soluble and biodegradable materials, evaluate the materials being brought to market, and provide a landscape of solution providers.
Detergent pods alone are a single-digit billion-dollar market that continues to grow as consumers become more aware of the performance benefits pods offer. Water-soluble pods are often made from polyvinyl alcohol (PVA), but many brands are looking to replace PVA with alternative materials, especially ones that are bio-based or made from waste feedstocks. While these alternatives are unlikely to compete with PVA-based polymers for all applications, they could be competitive in applications like single-use pods, especially for high-end brands that can easily absorb a premium. Moreover, edible materials can open up the use of pods in food applications.
Notable startups here include the following:
- Lactips (France) positions its casein-derived materials as a replacement for PVA. The company sources its feedstock directly from the dairy industry and recently received €13 million to construct its new production plant, doubling its capacity to 3,000 tpa. Because casein-derived materials are lower in molecular weight, they do not have the same mechanical strength as PVA materials, limiting their applications.
- Decomer (Estonia) produces edible and water-soluble packaging made from plant protein. Its first product will be water-soluble honey packages called "honey drops" for tea or coffee. The company is also developing blendable packages for smoothies, water-soluble flavor packets (for soups like ramen), and single-use detergent pods for laundry.
- SoluBlue (U.K.) uses an algae-based material that it claims can easily be degraded by bacteria. It's aiming at cup applications in the short term but is considering entering detergent pods as well. An earlier iteration of its technology from 2017 claimed the packaging would dissolve in water at room temperature in between five minutes to 15 minutes, depending on thickness.
Disposable plastic shopping bags pose huge environmental and health problems, especially in developing countries, where they block waterways and create or exacerbate flooding. Trillions of plastic bags are still consumed worldwide each year, mostly made from polyethylene or materials that are slow to degrade. More than 60 countries have introduced bans and levies to curb single-use plastic waste, often focused on plastic bags. Numerous startups are developing water-soluble alternatives, as these materials could be exempt from many of the bans. Some materials claim similar performance to polyethylene and can be extruded in any plastic extrusion machine, but a key challenge is performance in wet or humid environments. While water solubility is a great attribute for end of life, consumers don't want shopping bags that will break or dissolve when it rains.
Notable startups include:
- H2OK (Hong Kong) produces water-soluble bags made from PVA that are soluble in water at 60 °C. The company targets a variety of bag types for supermarkets, clothes, and garbage.
- Aquapak (U.K.) produces a PVA polymer blend for thin-film packaging applications and argues that, due to a modified production process, the material can achieve the same performance as polyethylene with a thinner film that is water-soluble. The material is produced in a recently established commercial facility with a 30,000 tpa capacity in Rubery, England.
- Wave Eco-Solutions (Netherlands) produces a bio-based, biodegradable, and hot water-soluble plastic bag from cassava starch. The bag dissolves in room-temperature water in a span of about three months, or instantly at temperatures of 80 °C or higher, leaving a liquid that is 100% natural and even drinkable.
- Solutum (Israel) produces water-soluble bags, starting with trash bags and bags for the cement, food, and packaging industries, though available information about its tech is limited.
- Hydroplast (Hong Kong) developed a water-soluble, biodegradable, and nontoxic polymer it hopes can replace single-use bags for shopping, laundry, and retail. Specific details around this technology are unclear.
The global market for wet wipes is in the double-digit billions of dollars. While wet wipes marketed as "flushable" have received a significant amount of interest from consumers, they often don't break up as well as toilet paper and have caused major sewer blockages in areas of the U.S. and the U.K., leading to hundreds of millions of dollars of damage. A large part of the issue is that manufacturers have not designed for multiple wipes to be flushed at the same time. While there is a need to develop solutions that can more readily dissolve, historical challenges with "flushable" wipes may interfere with their adoption, especially if unfavorable regulations are passed.
- Polipop (U.K.) makes flushable and biodegradable sanitary products. It claims its pads are highly absorbent and stable when exposed to blood and will only disintegrate when exposed to freshwater.
- McCormack Innovation (U.K.) develops water-soluble wet wipes. The company aims to target medical, personal care, and cleaning product sectors. It has also developed a wet wipe that is effective against viruses, including the coronavirus.
A wide range of water-soluble and biodegradable materials are available, but each will be best-suited for certain applications, given that each target use has different performance requirements. Nevertheless, the majority of these materials will be limited to niche applications given their higher costs – which is a particular challenge for plastic bags, a high-volume, low-margin market in which the higher costs will be challenging, perhaps even with regulatory support from bag bans or mandatory bag charges.
Materials developers should consider developing materials solutions for higher-end applications like personal and home care where water solubility is an asset but wait and see if and how newer materials are adopted in bag applications, especially in regions where policy will come into play. Brands interested in sourcing water-soluble and biodegradable materials should evaluate performance first and consider how the use of such materials could change the way consumers interact with or store products, as it is often difficult to change consumer behavior and expectations.