Lowe, Samuel (2017) Branched polymers via CCTP with vinyl end groups and their application in wound care materials. PhD thesis, University of Warwick.

Preview

PDF WRAP_Theses_Lowe_2017.pdf - Submitted Version - Requires a PDF viewer. Download (7Mb) | Preview

Request Changes to record.

Abstract

Chronic wounds represent a significant problem to healthcare systems globally, wound generated from burns and diabetic ulcers have a 20 % chance of becoming chronic. In this thesis work was conducted to try and develop novel networks to act as chronic wound treatment systems.

Initially Catalytic Chain Transfer Polymerization (CCTP) was utilized to develop low molecular weight branched polymers with ω-vinyl end groups for use as novel gelators. Poly(methacrylic acid) (pMAA) was chosen as a building block due to its anionic nature and possibilities in the region of drug delivery and wound care. Branched acidic polymers of different molecular weights and degrees of branching were synthesized with good control. In addition to this branched and linear species of poly[(polyethylene glycol) methyl ether methacrylate] pPEGMEMA were synthesized by the same technique. All polymers were investigated kinetically and with multi-detector SEC to determine branching.

A poly(2-hydroxyethyl acrylate) hydrogel system was optimized by both thermal and photo initiation prior to the addition of branched acid polymers. Branched acid polymers exhibited a hardening effect upon thermally cured gels by rheology with a corresponding decrease in swelling suggesting reduction in the mesh size due to acting as gelators. However, in a photo-cure system the reverse effect was observed with softening and increase in swelling signifying an increase in mesh size.

A poly(2-acrylamido-2-methylpropane sulfonic acid) (pAMPS) hydrogel system was then utilized to study this effect with different degrees of branching and molecular weights of polymers. Studies by rheology, swelling and compression indicate that the branched acid polymers were exhibiting a chain transfer effect from the ω-vinyl end group, inhibiting gel formation and therefore rendering them unsuitable for use as gelators.

An inter-penetrating network (IPN) of pAMPS and a thermoplastic elastomer (TPU) was formed by photo-curing a TPU film swollen in a solution of AMPS monomer and initiator. This process yielded a versatile, highly absorbent and transparent network which was able to rapidly absorb large quantities of fluids. Calcium testing and adhesion testing showthat this material has significant potential in the field of wound dressings.

Item Type:	Thesis (PhD)
Subjects:	Q Science > QD Chemistry
Library of Congress Subject Headings (LCSH):	Branched polymers, Polymers in medicine, Polymerization -- Research, Surgical dressings, Colloids in medicine
Official Date:	May 2017
Dates:	Date Event May 2017 Submitted
Institution:	University of Warwick
Theses Department:	Department of Chemistry
Thesis Type:	PhD
Publication Status:	Unpublished
Supervisor(s)/Advisor:	Fox, David J. (David John)
Format of File:	pdf
Extent:	xxiv, 212 leaves : illustrations, charts
Language:	eng

Request changes or add full text files to a record

Repository staff actions (login required)

View Item

Downloads