Publikationsserver der RWTH Aachen University
Multi-functional polymers from polyamines and functional five-membered cyclic carbonates
Abstract
dc:descriptionThis dissertation is concerned with the synthesis of functional polymers prepared by ring-opening reaction of functional five-membered cyclic carbonates with polyamines. The functionality of the polymers defines their properties and their application: multi-functional poly(ethylene imine)s for antimicrobial polymer and primer polymer for textile finishing were prepared. The main concept for the synthesis of multi-functional polymers comprises the coupling of two (functional) amines using a dicarbonate linker, (2-oxo-1,3-dioxolan-4-yl)methyl phenyl carbonate (I). This molecule has two electrophilic sites with different reactivity: a highly reactive phenyl ester carbonate and a less reactive alpha-glycol carbonate. At low temperature, the phenyl ester carbonate reacts with an amine and forms a urethane group; it should be noticed that the only observed leaving group is phenol. The cyclic carbonate reacts via ring-opening at slightly higher temperature but only after total consumption of the phenyl ester carbonate. According to this observation, the dicarbonate I was reacted with an equimolar amount of the desired amines to prepare functional cyclic carbonates (II). Functional cyclic carbonates (II) were prepared also from (2-oxo-1,3-dioxolan-4-yl)methyl chloroformate (III) and from 3-chloro-1,2-propanediol (IV). More than 20 different cyclic carbonates bearing different functional groups such as hydrophobic chains of various lengths, ammonium groups, sulfonate groups, amphiphilic groups, reactive groups, and labeling groups (benzyl, pyrene, and fluoresceinamine), were prepared. If the ring-opening reaction of these functional cyclic carbonates with several polyamines such as poly(vinyl amine), poly(allyl amine), poly(ethylene imine), and polylysine, were investigated, only reactions with poly(ethylene imine) (PEI) gave satisfactory results for both cationic and hydrophobic functional carbonates in terms of high conversion of the primary amine groups of the polymers and absence of side reactions. Multi-functional PEI can be obtained in a one-step synthesis by reaction with different functional cyclic carbonates. Amphipathic polymers act as antimicrobials, thus PEI was functionalized with cationic and hydrophobic groups. In order to study the structure–properties relationship of these water-soluble amphipathic PEIs, different parameters were varied: (i) the molecular weight of PEI, (ii) the ratio of alkyl to cationic groups, (iii) the length of the alkyl chain, (iv) the structure of the hydrophobic group, branched or not branched, (v) the nature of the ammonium group via substitution of a methyl group by long alkyl group. The critical aggregation concentration, the hydrodynamic radius and the minimal inhibitory concentration of the obtained polymers were determined in order to better understand the correlation between the physical properties of the polymers and the interaction with the biological membranes. For antimicrobial coatings two different approaches were considered: (i) water insoluble polymers (but soluble in organic solvents) such as PEI functionalized with octadecyl chains and cationic groups and (ii) water soluble polymers bearing reactive allylic, cationic and hydrophobic groups which after coating were thermally cross linked.
Degree
thesis:*- Grantor dc:publisher
- Publikationsserver der RWTH Aachen University
- Year dc:date
- 2008
Author and committee
dc:creator, dc:contributor.*- Author dc:creator
-
- Pasquier, Nicolas
- Contributors dc:contributor
-
- Möller, Martin
Subjects
dc:subject × 9Rights
dc:rights- Statement dc:rights
-
- info:eu-repo/semantics/openAccess
- Language dc:language
- eng