Neutron Radiography Conversion Screen With Acrylic Resin

Neutron radiography is an important technology of non-destruction testing. The quality of neutron radiography is deeply influenced by the property of the converter. As the binders for the converter, the water-soluble acrylic resin posses not only excellent hardness, gloss, resistance of water, acid, alkali and weather which is the advantages of and organic solvent resin, but aslo the low price, the use safety, energy saving and reducing environmental pollution.The water-soluble acrylic resin is synthesized with the solution polymerization. And it is prepared via solution polymerization which takes acrylic acid, methyl methacrylate, acrylic acid butyl ester and methyl acrylic acid hydroxy ethyl ester as the monomers, takes benzoyl peroxide as the initiator and takes n-butanol as the solvent. By discussing initiator's amount, solvent and monomers' allocated proportion, acrylic acid's amount, instilment time, heat preservation time,neutralization degrees and reaction temperature to the resin's performance influence, such as the water-solubility, the light transmission rate, the content of the firm, the conversion rate and the viscosity, we obtain the formula of synthesis water-soluble acrylic resin for neutron radiography converter: the AA amount used is 11%, the HEMA amount used is 20%, the BPO amount used is 2.0%, the MMA:BA (mass ratio) is 1:1, the solvent: monomer (mass ratio) is 1:1; and the synthesis conditions: the monomer dropping time is 3h, the sintering time is 2.5h, the reaction temperature is 110℃, ammonia is used as the neutralizer and the neutralization degree is 90%.The function of the resin which made under conditions of formula and conditions above-mentioned as follows: It is light yellow transparent liquid, it has good water-solubility, visible light transmittance of its 40% aqueous solution is 98%, its conversion is 96%, viscosity of its 40% aqueous solution is 3.12mPa·s, and its glass transition temperature is 46.1℃, the thermal decomposition temperature is 360-440℃.Synthetic resin and reaction material are well-mixed, the neutron radiography converter is produced by means of screen printing. The test results showed that this converter exhibits good resolution and sensitivity after radiography.