Doctoral Thesis. Development of Renewable Feedstock Based Rigid Polyurethane Foam and Nanoclay Composites

To be granted the scientific degree of Doctor of Science (Ph. D.), the present Doctoral Thesis had been submitted for the defence at the open meeting of RTU Promotion Council on September 3, 2020 at 14:00 at the Faculty of Materials Science and Applied Chemistry of Riga Technical University, 3/7 Paula Valdena Street , Room 272.

PhD Miķelis Ķirpļuks is researcher of the Polymer Department of Latvian State Institute of Wood Chemistry. The Ph. D. Thesis was developed in the Polymer Department of Latvian State Institute of Wood Chemistry.

Scientific supervisors: Dr.sc.ing. Uģis Cābulis (LSIWC), Dr.sc.ing., Asoc.Prof. Sergejs Gaidukovs (RTU).

Rigid PU foams are versatile material commonly applied as a thermal insulation material. It can be applied as an impact absorption material in the automotive industry if material with sufficient mechanical properties has been developed. Further increase inmechanical properties can be achieved by developing nano-reinforced rigid PU foams. Majority of commercially used rigid PU foams are produced from non-renewable petrochemical-based raw materials. Although, renewable feedstock, as well as recycled materials,can be used to obtain rigid PU foams with equal properties. In this work,several bio-based, as well as APP polyols,have been used to develop rigid PU foams. Rigid PU foam thermal insulation material has to fulfil demanding flammability requirements. This is achieved by the introduction of different flame retardants into the material structure from which most common are halogenated flame retardants. Halogenatedflame retardants are associated with different health hazards, thus their phase-out from the market can be expected. A good alternative to halogenated flame retardants areintumescent flame retardant solutions.

PhD thesis available: https://ortus.rtu.lv/science/lv/publications/31088 (English, summary - Latvian, English).