How Spider Silk Led to a Replacement for Single-Use Plastics

Spider silk is stronger than steel and tougher than Kevlar. Pound for pound, spider silk is five times stronger than steel and it’s also flexible and stretchable. When studying protein formation relating to human diseases such as Alzheimer’s, scientists at the University of Cambridge became interested in the strength of spider silk despite is weak molecular bonds. (Weak bonds don’t share electrons between atoms as do much stronger covalent bonds.)

While trying to replicate the bond formation using soy protein isolate, they created a product that looks similar to plastic but can be made from plant proteins (no spiders required). The material is water resistant, durable and fully compostable. It can be used in place of engineered plastics such as low-density polyethylene, the material used to make single-use plastic bags.

Not only are single-use plastics a huge pollution problem, they’re also made from petroleum-based chemicals, releasing more greenhouse gases into the atmosphere. Difficult and costly to recycle, they usually end up in landfills or oceans where they break down into toxic particles that contaminate the soil and enter the food chain when animals accidentally ingest them.

A group of researchers from the University of Cambridge spun off from the school to create Xampla, a company developing natural and biodegradable materials to replace plastic film, coatings, microcapsules and packaging. The first vegan spider silk single-use sachets and capsules will be released this year, for use in dishwasher and laundry tablets.