Exploring the potential of inexpensive high oleic sunflower oil for new polymeric architectures

Abstract

AbstractBicomponent polymeric architectures were fabricated through visible‐light polymerization starting from methacrylated and PEGylated high oleic sunflower oil (HO‐SFO) monomers and compatible polyethylene glycol dimethacrylate (PEG‐DMA) capable of swelling in biological simulated fluid. Conversion of the methacryl moieties in the photo‐polymerization reactions was monitored by FTIR spectrometry and also gel fraction measurements. The amount of PEG‐DMA co‐reactant and PEG units grafted on the HO‐SFO backbone were found to directly influence the key properties of the oil‐based polymers. DSC measurements proved that higher content of PEG‐DMA (1:1wt, related to HO‐SFO monomer) influence the crystallinity degree, favoring also the increase of PBS absorption capacity. PEG chains from the HO‐SFO structure acts as mediator for the hydrophobic and hydrophilic components, influencing the system mobility, networks arrangement, affording the higher degree for PBS absorption (almost 70% after 50 days of immersion). For all the studied systems two‐phase absorption process was observed and assigned to the esters hydrolysis, yielding new –COOH and –OH groups, XPS and SEM confirming this hypothesis. Polymers degradation during PBS immersion conduce to the elimination of PEG oligomers and unreacted methacryl moieties from the fatty acids, by diffusion in the swelling medium, phenomenon supported by detectable architectural changes from the SEM images.