Research On The Construction And Performance Of Responsive Polymer/nanocomposite Antibacterial And Anti-adhesion Surface

The adhesion of bacteria on the surface of the material will inhibit or destroy the properties of the material,and further produce biofilm on its surface.In addition,the adhesion of bacteria on the surface of the material is also easy to cause infection problems,causing great harm to human health.The researchers found that supehydrophilic/superhydrophilic surfaces have excellent anti-fouling properties due to the hydration barrier effect,therefore,this strategy of constucting hydrophilic surface are used to build hydrophilic-type anti-adhesive surfaces.In addition,intelligent bacterially anti-adhesive surface has the ability of responding to environmental changes,so as to perform specific anti-adhesion means,is considered to be a new type of bacterially anti-adhesive strategy.However,at present,few research has constructed synergistic surface of antibacterial ability and bacterially anti-adhesion,and most intelligent bacterially anti-adhesive surface is in response to a single environmental change,can not cope with complex environmental changes.Therefore,in this paper,intelligent hydrophilic-type composite surface of antibacterial activity and bacterially anti-adhesion was constructed by spraying the functional polymer layer on the TiO₂ nanotube arrays.By testing and analyzing the microstructure,surface wettability,antibacterial properties and anti-bacterial adhesion of composite surfaces,the structure-activity relationship among the functional monomers,surface wettability,and bacterial anti-adhesion was established,and the effects of the temperature and ultraviolet irradiation on the antibacterial adhesion of the composite surfaces and their mechanism were revealed.?1?Using VCL as the thermo-responsive monomer,the PEGMA as hydrophilic anti-adhesive monomer,the as-prepared ADTA as antibacterial cationic monomer,the VTES as the adhesive monomer,the AIBN as the initiator,through,the thermo-sensitive antibacterial and bacterially anti-adhesive copolymer was synthesized by the free radical solution polymerization method.Using the titanium sheet as the electrode,the TiO₂ nanotube array was prepared by anodic oxidation.A series of antibacterial and anti-adhesive composite surfaces were prepared by spray-coating method.?2?Antibacterial and bacterial anti-adhesion property of the prepared composite surfaces were studied,the results demonstrated that the antibacterial and bacterial adhesion property were improved,and the number of bacteria adhered on the composite surface decreased with the increasing of the grafting polymer concentration,For the same surface,the bactericidal effect of E.coli was better than S.aureus.When the grafting concentration is 1mg/cm²,both the antibacterial and the bacterially anti-adhesive rate can reach more than 99%.The bacterially anti-adhesive mechanism of composite surface was explained by combining the relationship between the number of functional monomers on the composite surface and the surface wettability.The result of the antibacterial cyclic testing proved that the composite surface had excellent durability of antibacterial and bacterially anti-adhesive property.After seven test cycles,both the antibacterial and bacterially anti-adhesive rate maintained above 95%.?3?Enhanced bacterial anti-adhesion induced by thermo-response were studied,herein,the static and dynamic methods were employed to evaluate adjustable bacterial adhesion under different temperature.It was found that bacterial anti-adhesion was greatly affected by temperature responsive action,with the decreasing of the temperature from 55 to 4?,the bacterial anti-adhesion property of the composite surface was gradually improved,it could be explained by the switchable hydration-dehydration transition of thermoresponsive VCL segments,whose evidence could be observed through the change of AFM in the water phase and surface wettability at different temperatures?4?,37?and 55??,additionally,the interpretation mechanism of bacterial adhesion model induced by temperature response was established.?4?Enhanced bacterially anti-adhesion of antibacterial composite surface triggered by light-responsive action were also studied,The results demonstrated that TiO₂ nanotube array has the wettability reversible change in response to the ultraviolet light,so as to enhance the bacteria anti-adhesion property of the composite surface.It was also found that the bacterial adhesion of composite surface increased with the increase of irradiation time.When the illumination time reached 100 min,the bacterially anti-adhesive rate of the composite surface for E.coli on increased from 86.67%to 99%.it could be explained by the changes of surface elements,the EDX result demonstrated that oxygen elements of the composite surface after UV lighting significantly increased so as to increase the surface wettability.Thus the adhesion force of underwater oil of sample after illumination reduced,the bacterial adhesion behavior of the composite surface triggered by temperature response was explained by the proposed mechanism of the bacterial adhesion model.