Research On Preparation Of Hydrogel Microsphere-based Antibiofouling Composite Coatings

In recent years,ships and other equipment in oceans are contaminated by sea water,oil and microorganisms.In result,the performance and the service life is urgently needed to solve.Microorganisms,plants and other organic matters in oceans attached to surfaces of ships,breeding nets or cages with adverse effects on it,known as biofouling.The present antifouling coatings are including chemical antifouling,patterned antifouling hydrogels,etc.In this thesis,an antifouling coating with antifouling agents and hydrogels with rough structure is prepared.A polymer hydrogel is a kind of macromolecule or macromolecular aggregates with chemical or physical crosslinking structures,which can absorb large amounts of water but is not even soluble in water.It can maintain a definite shape and three-dimensional network structure in water and rapidly swell.Therefore,it is also called “water material”.This materials for antifouling at ships and marine equipments are of great significance for self-cleaning and anti-biological adhesion.The hydrogel studied in this paper is a natural polysaccharide alginate separated from brown algae.Its G-blocks are cross-linked into egg box structures by divalent metal ions to form a polymer hydrogel.In this work,divalent calcium ions were crosslinked with sodium alginate to form calcium alginate hydrogel microspheres.Under usage of a self-constructed electrospray ionization(ESI)device,and the sodium alginate solution is dripped into the calcium chloride solution in the form of tiny high voltage charged droplets,and calcium alginate hydrogel microspheres are prepared.The preparation method is simple and easy.Then the epoxy resin coatings of the calcium alginate hydrogel microspheres were coated with an epoxy resin to attain a good underwater superoleophobic performance,as well as stability under sea water and good mechanical properties.In this work,CuCl is encapsulated in gelatin microspheres for a slow release,and to achieve the purpose of sterilization.It is then made to the epoxy resin coatings of calcium alginate hydrogel microspheres.This composite coating,is having the property of underwater superoleophobic performance,it also provides the function of preventing biological adhesion.These produced hydrogel microspheres are stable under artificial sea water.At the end,an easily producible material for antibiofouling,with good mechanical properties is obtained.