The Prepartion And Application Of Adhesives For Elastic Bandages

At present adhesives applied to medical elastic bandages at home and abroad are mostly natural rubber latices or their modified products. Because the protein in the natural rubber latices can cause human body allergy and after placing for a long time can lead to corruption, mildew and metamorphic phenomenon, the study of steady adhesives without irritability to replace natural rubber latices is very important.Acrylate emulsion adhesives for medical elastic bandages were prepared with seed emulsion polymerization and graft modification technology. The effects of glass transition temperature(Tg), blending latices of different Tg, graft modification and other factors on the property of adhesives were studied. The experimental results showed that the adhesion fastness of adhesives can be adjusted expediently through blending latices of different Tg and graft modification technology, but the sense of touch of products needs to be improved. The adhesion fastness of adhesives was 1.10 N/25 mm when Tg of polymer was -50℃.The adhesive with best performances was prepared by blending latices with Tg of -45.5℃and -5.3℃in ratio of 2:1. In the study of grafting MMA, balanced results of ball tack and autohension were achieved by grafting 5% MMA.Solvent adhesives for bandages were prepared by using polyisoprene rubber and various additives as raw materials. The effects of polyisoprene rubber,tackifying resin,elastomer and filler on the property of adhesives for bandages were studied. The results showed that the autohension of polyisoprene rubber increased as its mooney viscosity increased and good sense of touch was also obtained. As the content of filler,polyethylene butyl acrylate (28BA-175) and tackifying resin increased, the adhesion fastness of solvent adhesives for bandages rose first and then fell sharply. The adhesive with best performances was prepared when the blending ratio of polyisoprene rubber,polyethylene butyl acrylate (28BA-175),silica hydrate,petroleum resin(LH100-0)and 120# gasoline was 16:4:1:2:77.The properties were as follows: viscosity 24500 mPa·s, tack 5.5 cm (7# steel-ball ), grade of touch 1, and adhesion fastness 1.33 N/25 mm.In order to meet the needs of safety and environmental protection, emulsification and solvent extraction technology were used in preparing solvent adhesives for bandages and water-based adhesives without irritability. The effects of emulsifier,defoaming agent,pH,temperature,time and pressure on property of products were studied. The results showed that more stable emulsion can be prepared by using mixed emulsifiers. The best mass ratio of oleic acid,NP-40,HP-08 and ethanolamine was 1.9:1.2:2.3:0.3.The emulsion with best performances was prepared under the conditions: oil-water ratio 2:1,emulsification temperature 40℃,water input rate 2 d/s,pH 9,concentration temperature 70℃,vacuum 0.05 MPa, and the storage stability of the emulsion after thickening is more than 6 months. The effects of post-processing on property of adhesives for bandages were also studied. The product with good touch and adhesion fastness can be obtained through post-processing. The properties were as follows: tack 6.5 cm (7# steel-ball ),grade of touch 1, adhesion fastness 1.09 N/25 mm.