Teflon could rightly be called one of the chemicals of the 20th century, making good on DuPont's promise to deliver "Better Living Through Chemistry". The use of polytetrafluoroethylene's (PTFE) non-stick and chemical resistant properties have become well known. Yet, no matter how widespread it and other low-surface energy plastics like polyethylene (PE) and isotactic polypropylene (iPP) have become, they remain inherently difficult to bond. At least the surfaces usually demand priming prior to joining and often they demand much more energy-intensive surface treatment.
One option for forming bonds with very low surface energy plastic substrates is through radical reactions that abstract hydrogen from their surface. This creates carbon centred radicals capable of initiating polymerization or of terminating an already growing chain. Acrylic adhesives can offer a means of doing this, when catalysed by trialkylboranes that promote polymerization and formation of carbon centred, oxygen-centred radicals.