Antimicrobial performance and the cure and mechanical properties of peroxide‐cured silicone rubber compounds

Abstract

Nanosilver colloid, Ag‐based zeolite compound, and 2‐hydroxypropyl‐3‐piperazinylquinolinecarboxylic acid methacrylate (HPQCAM) were used as antimicrobial agents and/or mechanical property improvers in peroxide‐cured silicone rubber vulcanizates. The vulcanizates were prepared by using a two‐roll mill followed by a hydraulic press in order to vulcanize the rubber compounds, and their cure characteristics, mechanical properties, and antibacterial performance were assessed. The antimicrobial performance of the silicone rubber compounds was examined through plate‐count‐agar and drop‐plate‐agar methods, as well as the halo test. The results suggested that the addition of all of the antimicrobial agents slightly increased the cure time, except for the Ag‐based zeolite. The addition of all of the antimicrobial agents also affected the mechanical properties of the rubber vulcanizates. The Ag‐based zeolite gave the silicone rubber compound with the most improved mechanical properties, whereas HPQCAM was the most effective antimicrobial agent, as determined by the occurrence of the inhibition zone and 99% reductions of Staphylococcus aureus and Escherichia coli. The changes in silicone rubber surface with the addition of antibacterial agent were shown by progressive decreases in water contact angle. This result was observed only for the HPQCAM agent and was associated with diffusion and the releasing mechanism of the HPQCAM to kill the bacteria. The optical lightness of the silicone vulcanizates decreased with increasing nanosilver content but increased with increasing amounts of Ag‐based zeolite or HPQCAM. J. VINYL ADDIT. TECHNOL., 19:113–122, 2013. © 2013 Society of Plastics Engineers

Effects of UV weathering on the mechanical and antibacterial performance of peroxide‐cured silicone rubber containing biocide HPQM

“…The antibacterial agents used include nanosilver colloids, silver‐substituted zeolite compound (SSZ), and 2‐hydroxypropyl‐3‐piperazinylquinolinecarboxylic acid methacrylate (HPQM). In terms of silicone rubber compound, work by Taptim and Sombatsompop clearly suggested that HPQM was the most effective antibacterial agent when comparing nanosilver colloids and SSZ agents due to its organic structure and chemical compatibility with the silicone. This statement contradicted the work of Kaali et al , which found that the addition of (Ag+)‐loaded zeolite to silicone rubber improved the antimicrobial performance of the silicone, a result which was caused by the formation of the OH bond due to moisture contact with the (Ag+)‐loaded zeolite.…”

Effect of organoclay and silver‐substituted zeolite on the mechanical and antibacterial properties of a silicone rubber filled with 2‐hydroxypropyl‐3‐piperazinyl‐quinoline carboxylic acid methacrylate

“…The viable cell counts of bacteria are the number of bacteria growth as a function of contact time. A decrease in viable cell count with contact time indicates the inhibition of the bacteria growth [16].…”

“…Our previous study [16] on the curing and mechanical properties, and antibacterial properties of silicone rubber filled with a wider range of antibacterial agents including nano-silver colloids, silver subtitled zeolite (SSZ), and 2-hydroxypropyl-3-piperazinyl-quinoline carboxylic acid methacrylate (HPQM) indicated that HPQM was most recommended for enhanced antibacterial performance with worsened mechanical properties. Therefore, this work aimed to improve the mechanical properties of the HPQM containing silicone rubber compound.…”

“…The agglomeration problem was solved by binding the silver into zeolite. In this research, HPQM and SSZ were loaded into silicone rubber for improving the antibacterial performance of silicone rubber compound and based on our previous work [16] the SSZ also improved the mechanical properties of silicone rubber compound. The effects of OC and silver substitute zeolite loadings on the mechanical properties and cyclic fatigue life of silicone rubber vulcanizate containing HPQM were measured.…”

Enhanced functionality of colloidal polyaniline/polyvinyl alcohol nanocomposite as an antibacterial agent

“…Biocidal polymers have the ability to kill microorganisms by acting as a source of sterilizing ions or molecules [1][2][3][4][5][6]. The use of polymeric antimicrobial agents have the advantage that they are nonvolatile, chemically stable, find it difficult to permeate through the skin of man or animal, and may enhance the efficacy of some existing antimicrobial agents and minimize the environmental problems accompanying the residual toxicity of the agents in addition to prolonging their lifetime [7][8][9][10].…”