Scientists from Germany and the Netherlands are researching new environmentally friendly PLA materials. The aim is to develop sustainable materials for optical applications such as automotive headlights, lenses, reflective plastics or light guides. For now, these products are generally made of polycarbonate or PMMA.
Scientists want to find a bio-based plastic to make car headlights. It turns out that polylactic acid is a suitable candidate material.
Through this method, scientists have solved several problems faced by traditional plastics: first, turning their attention to renewable resources can effectively alleviate the pressure caused by crude oil on the plastics industry; second, it can reduce carbon dioxide emissions; third, this Involves consideration of the entire material life cycle.
“Not only does polylactic acid have advantages in terms of sustainability, it also has very good optical properties and can be used in the visible spectrum of electromagnetic waves,” says Dr. Klaus Huber, a professor at the University of Paderborn in Germany.
At present, one of the difficulties that scientists are overcoming is the application of polylactic acid in LED-related fields. LED is known as an efficient and environmentally friendly light source. “In particular, the extremely long service life and visible radiation, such as the blue light of LED lamps, place high demands on the optical materials,” explains Huber. This is why extremely durable materials must be used. The problem is: PLA becomes soft at around 60 degrees. However, LED lights can reach temperatures as high as 80 degrees while operating.
Another challenging difficulty is the crystallization of polylactic acid. Polylactic acid forms crystallites at around 60 degrees, which blur the material. The scientists wanted to find a way to avoid this crystallization; or to make the crystallization process more controllable — so that the size of the crystallites that formed would not affect the light.
In the Paderborn laboratory, the scientists first determined the molecular properties of polylactic acid in order to alter the material’s properties, in particular its melting state and crystallization. Huber is responsible for investigating the extent to which additives, or radiation energy, can improve the properties of materials. “We built a small-angle light scattering system specifically for this to study crystal formation or melting processes, processes that have a significant impact on optical function,” said Huber.
In addition to scientific and technical knowledge, the project could deliver significant economic benefits after implementation. The team expects to hand over its first answer sheet by the end of 2022.
Post time: Nov-09-2022