Low-Shrink and UV-Curing House Connection Inliners

The project deals with the development of low-shrinkage and adhesive fiber-reinforced plastics for application as house connection inliners under UV curing.

The renovation of damaged house connection pipes is difficult due to the often limited accessibility, installed pipe bends and dimensional changes. However, solutions for rehabilitating damage to house connections are offered by special inliners made of composite materials for trenchless and non-destructive methods. For this purpose, a textile hose is first impregnated by a reactive synthetic resin. Then the semi-finished part is inserted into the to-be-repaired pipe using water or air pressure and turned inside out to be cured. The resulting “pipe-in-pipe” system can subsequently be cured, thus sealing the repair area. In recent years, the use of UV-curing reactive resins in the field of sewer renovation of house connections has made rapid progress. The UVcurable resins, which are used for this purpose, are characterized by their good processability and focused fast curing. However, a central problem has proven to be that a backward running of the system cannot be ruled out due to the volume shrinkage of the UV resins caused by the curing process, as well as a not always sufficient adhesion of the inliner with the different old pipe surfaces. In order to nevertheless achieve a tight system, additional complex sealing measures are currently carried out at the beginning and end of the pipe and at the side connections. The aim of our research work is therefore the development of low-shrinkage as well as adhesive fiber-reinforced plastics that avoid the additional and costly process steps, resulting in a faster, lower-risk and more economical process. Thermo-modulated optical refractometry is used as a new physical method for this purpose. It offers direct access to measurement data of the process-related volume expansion or shrinkage of the material.

Field of competence

Industry sectors

Project status

  • Current




Maurice Gilberg

Wiss. Mitarbeiter Tailored Thermosets & Biomaterials

Telephone: +49 631 2017 348


The project “nanUVation – Development of Shrinkage-Reduced as well as Adhesive Fiber-Reinforced Plastics for Application as House Connection Inliners under UV Curing” is funded by the Federal Ministry of Economic Affairs and Energy on the basis of a decision by the German Bundestag (funding reference ZF4052327).