Synthesis and Hydrolysis of glycine-containing Polyoxalates
2026 (English)Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE credits
Student thesisAlternative title
Syntes och hydrolys av glycinhaltiga polyoxalater (Swedish)
Abstract [sv]
Polyoxalater är en polymerklass som hydrolyserar snabbt, och som har potential att användas i nedbrytbara medicinska implantat. Glycin är en essentiell aminosyra med antiinflammatoriska egenskaper. Vi har utvärderat stegvis polymerisation av dimetyloxalat, 1,3-propandiol och glycinmetylester som en syntesväg till hydrolyserbara polymerer för kontrollerad frisättning av glycin. Utan glycin kunde polymerer med acceptabel molekylvikt bildas. Glycinhaltiga polymerer erhölls också, men syntesen av dessa polymerer försvårades av ett antal sidoreaktioner, vilka utgör hinder för framtida tillämpningar. Hydrolysexperiment kunde dessutom visa att frisättning av glycin inte uppnåddes; trots att produkterna var delvis hydrolyserbara fanns inte ren glycin bland de lösliga nedbrytningsprodukterna.
Gemensamt för problemen med polymerisation och hydrolys var de stora reaktivitetsskillnaderna mellan oxalatestern och glycinets ester, men polymerisationen påverkades även starkt av i vilket oxidationstillstånd glycinets amin är när det tillsattes. Polymererna uppvisade även ett motstånd till såväl upplösning som rekristallisering, vilket kraftigt försvårade deras upparbetning.
Abstract [en]
Polyoxalates are a class of polymers with rapid hydrolysis, which have potential to be applicable in degradable medical implants. Glycine is an essential amino acid with anti-inflammatory properties. Polymerisation of dimethyl oxalate, 1,3-propanediol, and glycine methyl ester was evaluated as a method of synthesising hydrolysable polymers for controlled glycine release. Without glycine, polyoxalates were formed with acceptable molecular weights. Glycine-containing polymers were also formed, but the polymerisation was associated with severe difficulties, which in turn made the analysis of the products challenging, and which would also hamper practical use. Hydrolysis experiments also showed that glycine release was not achieved; although the products were partially sensitive to hydrolysis, no pure glycine could be identified among the soluble degradation products.
The great difference in reactivity between the oxalic ester and the glycine ester contributed to both the low degree of polymerisation and the incomplete hydrolysis. Additionally, polymerization was significantly affected by the oxidation state of the added amine. The polymers also demonstrated resistance to both dissolution and reprecipitation, which greatly hampered their work-up.
Place, publisher, year, edition, pages
2026.
Series
TRITA-CBH-GRU ; 2026:025
Keywords [en]
polyoxalate, polyoxamide, glycine, hydrolysis, step-wise polymerisation
Keywords [sv]
polyoxalat, polyoxamid, glycin, hydrolys, stegvis polymerisation
National Category
Polymer Chemistry
Identifiers
URN: urn:nbn:se:kth:diva-376567OAI: oai:DiVA.org:kth-376567DiVA, id: diva2:2037040
Subject / course
Polymeric Materials
Educational program
Degree of Master - Macromolecular Materials
Supervisors
Examiners
2026-02-102026-02-10