Class 6 Science RESPONSE TO STIMULUS – Erudex Learning App
Researchers have created a paper-like material from pollen that bends and curls in response to changing environmental conditions.
Currently, many sensors and actuators based on artificial synthetic materials have been developed, but they have a rather high cost and are not environmentally friendly. Therefore, materials scientists from Nanyang Technological University decided to create a material from hard grains of plant pollen..
To make paper, scientists first turned tiny grains of sunflower pollen into a flexible, gel-like material. In a soap-like process, the team removed the sticky, oily coating from the beans and then immersed them in an alkaline solution for several hours. After further casting and drying of the resulting microgel, a paper-like material is formed..
Using scanning electron microscopy, the scientists discovered that this paper is composed of alternating layers of pollen particles, with the top layer being significantly rougher than the bottom. When In contact with water or steam, these pollen particles in the material swell and expand, but due to structural differences, they do this in different ways. Irregular changes cause internal stress across the thickness of the paper, causing it to bend.
To demonstrate the properties of the pollen-based material, the team folded it into a flower that opened up under the influence of water vapor. Scientists have also shown that the physical properties of paper can be controlled by exposure to an alkaline solution and a combination of several layers. For example, a two-layer strip of material can independently roll or move like a caterpillar, alternately expanding and contracting.
According to materials scientists, this natural material demonstrates the potential for the development of a wide range of individualized actuator systems for a variety of functional needs, including soft robots, sensors, artificial muscles and electrical generators..
Scientists have also recently made a film material that converts natural sunlight into mechanical work without additional equipment..
text: Ilya Bauer, photo and video: Nanyang Technological University