LONDON: Details related to how a spider adapts to its environment’s humidity and changes web viscosity may assist in developing stronger adhesives in the future. Spiders enhance web glue viscosity by relying on the humidity of their environment to boost the capture of prey, said researchers. Researchers noticed that 7,500 out of 45,000 known species of spiders spin webs to catch prey, and that web silk is made up of an axial fiber coated with glue-like droplets.
According to the researchers, what makes the web so special is that its adhesion is based on humidity. In contrast, synthetic glue weakens when it comes in contact with moisture in high humidity. Scientists hope that what they have learned about spider webs will help them develop better forms of glue using the spider’s technology.
Researchers from the University of Akron, Virginia Polytechnic Institute experimented with the connection between the web glue and humidity-dependent viscosity. Gaurav Amarpuri of Akron stated that the team measured the glue’s viscosity and its link to humidity, and used imaging to study the glue droplet spreading rate. The team did this for five spider species.
The team said that a liquid droplet’s spreading follows a “law” in which low adhesive droplets spread more quickly than ones with high adhesiveness. By using this “law”, they concluded that the glue is strongest at high humidity levels.
The team also examined the glue under a microscope, particularly its peeling factor, and discovered that its extensibility grows with humidity. Amarpuri said the glue adhesiveness showed “…changes of over five orders of magnitude with a shift from 30 percent to 90 percent relative humidity — the equivalent of a solution changing from the consistency of peanut butter to that of olive oil.”
