Surface modified polymers to introduce antibacterial activities

This thesis is concerned with the chemical surface modification of several commercial industrial polymers in order to introduce antibacterial activity. Surface modification of polymers including LDPE, PE-fibre, MDPE, UHMPE and PS-XAD4 by carbene insertion reaction and diazo coupling was carried out using two diazo systems, urea diaryl diazo system and bis (dimethylamino) diaryl system. Successful surface modification on polymers was achieved while bulk properties of polymers were maintained. ATR IR and combustion analysis were used to characterize modified polymer. Clear ATR IR absorption peaks and colour change during diazo coupling indicated successful surface modification. Surface coverage of modified polymers was calculated using nitrogen content detected by combustion analysis. Modified polymers binding with several biocidal agents including hydrogen peroxide, bleach and penicillin V were prepared and antibacterial activity was tested against S. aureus and E. coli. Modified polymers using the urea diazo system showed negative bioassay results, while modified polymer using the bis (dimethylamino) diaryl system showed excellent antibacterial activity.