New composite gypsum plaster – ground waste rubber coming from pipe foam insulation

• A lightweight composite is obtained with the addition of waste rubber to gypsum.
• There is physical compatibility between gypsum and pipe foam insulation waste rubber.
• This composite can be part of the core of plasterboards used in construction.
• Mechanical strength decreases with an increase in waste rubber addition.
• Samples’ flexural strengths with different waste proportions fulfill EN Standards.

Industrial production of pipe foam insulation generates huge volumes of scrap material, driving to a serious environmental problem.This research studies the potential of adding different size particle proportions of this waste rubber to a plaster matrix. For this purpose, an experimental plan has been elaborated which characterizes the physical and mechanical behavior of the new composite: Shore C hardness, flexure and compressive strength. Furthermore, different particle sizes, weight rates and water/plaster ratios have been analyzed.In view of the results this waste rubber could be incorporated in gypsum based composites forming part of new lightweight products.