In the frame of the collaborative European Project SUNRISE (grant agreement nº958243), LENZ INSTRUMENTS has developed a novel solution for the inspection of Polyvinyl Butyral (PVB) in laminated glass.
PVB is a noncross-linked thermoplastic used as interlayer film in the production of laminated glass, which is widely used in automotive and architectural applications. A thin interlayer PVB film is sealed between two glass panes, leading to a “sandwich” structure which is optically transparent, and mechanically tough. PVB confers laminated glass unique mechanical properties in terms of impact resistance, and acts like a binding element in case the glass is broken.
Despite its functional advantages, laminated glass poses environmental concerns. Only in Europe, it is estimated that around 480,000 tons of laminated glass are landfilled, due to the lack of effective recycling techniques. Moreover, while some emerging recycling technologies are currently under development, the accurate classification and characterization of end-of-life laminated glass materials is essential in order to optimize the recycling processes, as well as to maximize the value of the recovered material.
To address this problem, LENZ INSTRUMENTS has developed a novel inspection solution for laminated glass, which is currently at the demonstrator stage. This solution is based on the combination of different sensing techniques, including near-infrared transmission spectroscopy (NIRS), and the implementation of Artificial Intelligence (AI) techniques, to assess key optical and physical properties of the PBV interlayer.
The SUNRISE inspection system for laminated glass consists of a conveying system that continuously drives the glass panels into the inspection volume. In a few seconds, the AI algorithms assess the optical properties of the PVB interlayer film (haze and yellowness), and determines its chemical composition (type of plasticizer). Based on the results of the analysis, glass modules can be sorted into different grades or categories, and processed using specific recycling processes.