Study On Preparation And Properties Of Magnesium Acrylate Waterproof Material

At present,some large-scale projects,such as the development of water conservancy and hydropower,the construction of coal mines,geological exploration and the waterproof engineering of urban underground engineering,will appear various degrees of damage or deformation with the change of time.The main problem is that the problem of underground leakage and the common small crack grouting has not been completely solved.Magnesium polyacrylate waterproof material is a new type of waterproof material.It is non-toxic and pollution-free,and its construction method is simple.It is a very suitable and excellent waterproof material for crack repair.However,due to the poor storage stability of the current magnesium polyacrylate waterproof materials,the duration of various projects is different,so it is necessary to study the magnesium polyacrylate based waterproof material with good storage stability and controllable construction period.Based on this,the preparation and curing properties of magnesium acrylate based waterproof materials were studied.In this paper,acrylic acid and magnesium oxide were used as basic reactants to prepare magnesium acrylate monomer solution through acid-base neutralization.The influences of initial reaction temperature,reaction time,feeding method and reactant type on the preparation of magnesium acrylate monomer solution were studied.The curing of the prepared magnesium acrylate monomer solution was studied.Magnesium acrylate monomer solution was used as the main agent and oxidants were added,Reducing agent,such as: sodium bisulfite,triethanolamine;Crosslinking agents,such as N,N '-methylene diacrylamide;Amounts of fillers,such as talc,fly ash,silica fume,etc.,are used to make magnesium acrylate monomer solution undergo free radical polymerization at room temperature and solidify it.The influences of the type,dosage,ratio,amount of oxidant and reducing agent,the amounts of crosslinking agent and the types and amounts of filler on the curing time and related properties of colloids were studied.The results show that: in the preparation of magnesium acrylate monomer solution,the method of slowly adding magnesia aqueous solution to acrylic acid is selected to prepare at room temperature,the reaction time should be controlled at about 35 minutes,and the monomer concentration should be 30%.The higher the concentration of magnesium acrylate monomer solution is,the worse its stability is.When the concentration is more than 30%,the system is prone to self polymerization;when preparing magnesium acrylate solution,a large amount of polymerization heat will be released,and no water bath heating is required.When the reaction time is prolonged,the system is prone to self polymerization.The temperature and time of the monomer solution prepared by the above methods can be controlled,the reaction completion degree is high,and the storage stability of the synthesized magnesium acrylate monomer solution is good,so it is not easy to self polymerize.When the magnesium acrylate monomer solution is solidified,the initiation efficiency of sodium persulfate sodiumbisulfite oxidation-reduction system is larger and the curing time is shorter;the initiation efficiency of ammonium persulfate triethanolamine system is smaller and the curing time is longer;when the amount of oxidant is increased,the curing time is shorter;when the amount of oxidant is increased,the curing time is longer,but when the amount of reducing agent is increased,the curing time is longer,but when the amount of reducing agent is less than 0.5%Reducing agent can promote the production of free radicals and reduce the concentration of free radicals,which makes the curing time longer.When the amount of oxidant is determined,the larger the ratio of oxidant and reductant is,the shorter the curing time is and the greater the swelling degree is.As the amount of crosslinking agent increases,the curing time becomes shorter,and with the increase of the amount of crosslinking agent,the swelling degree and expansion rate of the gel in water both decrease,and the thermal stability is relatively good.The greater the compressive strength of the gel's solid sand body is,the higher the permeability coefficient is,and the worse the freezing-thawing resistance is.Different kinds of fillers and different amounts of fillers also affect the properties of gels.When talc powder is used as filler,compared with fly ash and silica fume,the tensile strength and elongation at break of gel with 3% talc powder are higher,and the elasticity of gel is better.For corrosion resistance,the gel with fly ash and silica fume has poor corrosion resistance,and even the gel is broken.The amount of 3% talcum powder corrosion resistance is better.Through the study of the preparation and curing of magnesium acrylate monomer solution,the best preparation conditions of magnesium acrylate monomer solution were obtained,the concentration of magnesium acrylate solution was controlled and stable storage was realized;by adjusting the type and dosage of oxidation-reduction system,the best formula of polyacrylate waterproof material was obtained,and the polymerization with controllable curing time and good comprehensive performance was obtained Magnesium acrylate gel.