Preparation And Properties Of Hydrophobic Association Hydrogels Reinforced By Particles

As a kind of soft and wet material,hydrogels have attracted wide attention of the researchers in tissue engineering,biological medicine,water-retention material,environmental engineering and so on.However,the traditional chemically crosslinking hydrogels are weak and brittle due to the lack of effective energy dissipation mechanism,and these hydrogels lack functional applications.Therefore,preparing tough hydrogels with functional applications has become an urgent problem.The tough hydrogels were successfully fabricated by introducing poly?butyl acrylate?latex particles and titanium dioxide nanoparticles into the hydrophobic association system,and the feasible application in photocatalytic degradation of dyes was also investigated in this article,including two parts of exploration work as follows.The first part of the work,we fabricated the particles toughened hydrogels by introducing the PBA LPs into the hydrophobic association system as hydrophobic association centers to induce effectively aggregation of hydrophobic chains.The effects of the PBA LPs contents and hydrophobic alkyl chain length on the mechanical properties of hydrogels were investigated.The results indicated that the optimal hydrophobic alkyl chain was lauryl?C12?.The fracture energy of the resulted hydrogels was 8.26 MJ/m³ and the tensile strength could reach 1.2 MPa,which was 2.1 times higher than the hydrophobic association hydrogels.The introduction of latex particles remarkably improved the mechanical performance,which presents a new thinking for preparing tough hydrogel.The second part of the work,the titanium dioxide/hydrophobic association?TiO₂/HA?composite hydrogels were fabricated by combining the TiO₂ and HA system via one-pot in situ photo-polymerization.The Ti O₂ acted as photoinitiator and crosslinking point.The Ti O₂/HA composite hydrogels exhibited excellent mechanical properties as well as photocatalytic degradation for dye.The fracture strength of composite hydrogels was 309kPa,which was 28 times higher than the HA hydrogels.Also,the composite hydrogels exhibited excellent effect in photocatalytic degradation of dyes and long service lives,with a maximum degradation rate of 96.63%.This work provides a theoretical basis for the study of toughened hydrogel and the development of photocatalytic technology.