Enzyme catalysis towards bio-based UV-curable buildingblocks
Time: Fri 2019-09-27 10.00
Location: M3, Brinellvägen 64, Maskin, våningsplan 2, KTH Campus, Stockholm (English)
Subject area: Biotechnology
Doctoral student: Maja Finnveden , Industriell bioteknologi, Biokatalys
Opponent: Professor Katja Loos,
Supervisor: Docent Mats Martinelle, Industriell bioteknologi
Abstract
Polymeric materials are found in virtually all areas of daily life; they are found in everything from packages keeping our food safe to the buildings where we spend our days, and the production is a worldwide industry. Although polymeric materials play a big part in sustainable solution’s, a lot can be done to develop more environmental methods for producing them. Both the process conditions and the resources that go in are important to consider. As more people understand that we need to manage our planet’s resources and ecosystem differently the demand for sustainable materials is increasing.
Catalysis is a key for designing chemistry for the environment and an interesting alternative is enzyme catalysis. Enzymes are proteins working as catalysts in biochemical reactions. One of the most prominent features of enzymes’ is their selectivity, which means that they have preferences towards forming one product over others. Using enzymes’ as catalysts in synthetic chemical reactions the selectivity can be used to produce a wide range of products without side reaction occurring. Further benefits of using enzyme catalysis include high rate acceleration and working under mild reaction conditions.
In the work presented here the selectivity and efficiency of enzymes have been combined with photochemistry in new efficient methods for the synthesis ofpolymeric materials. The enzymes used were the well-known lipase B form Candida antarctica and an esterase/acyltransferase from Mycobacterium smegmatis.
The thesis divides into three parts in which three kinds of components were synthesized by enzyme catalysis: (i) unsaturated polyesters; (ii) vinyl ether building-blocks; and (iii) bio-based polyamides. In the first two parts the efficiency and selectivity of enzyme catalysis at low temperatures were utilized to synthesize building-blocks that can be further used for photopolymerization. By using enzyme catalysis structures that can be difficult or even impossible to access with conventional chemistry have been made. In part (iii) photochemistry was used to synthesize a monomer that was polymerized by enzyme catalysis to produce polyamides.
All three parts presented in this thesis show the potential of the combination of enzymes and photochemistry to give access to polymeric materials under benign conditions. The work thus advances the capacity to manufacture building-blocks to create new sustainable polymeric materials.