Studis On Water Glass As Surface Sizing Agent To Improve The Strength Of Corrugated Paper

In this paper, water glass or water glass compound organic film components was employed as the surface sizing agent to improve the strength of corrugated paper. This paper includes three parts.Firstly, the viscosity of water glass at different temperatures and the hardening methods which affect ring-crush strength of corrugated paper, and the parameter of water glass modulus that affected the strength of the paper board were all discussed. The waterproof performance was discussed and improved. Compared with conventional surface sizing agents, water glass could apply a higher sizing load on paper and therefore a much higher stiffness of paper could be achieved. It could increase the ring-crush strength of corrugated paper to 161.7%.Secondly, water glass was blent with starch or styrene-acrylate emulsion to improve the strength of corrugated paper. The viscosity of compound system and its impact on ring-crush strength and bursting strength of corrugated paper were discussed, and Cobb value was used to characterize the waterproof performance of paper after surface sizing. At last, an optimization scheme has got. Water glass blending with 33% starch and 5% silicone oil allowed ring-crush strength and bursting strength of corrugated paper to increase by up to 91% and 50% respectively, and the requirements of use could be met.Thirdly, paper porosity, paper aperture and contact angle were employed to characterize the porous structure and surface wetting properties of paper, and the paper waterproof mechanism was discussed and analyzed based on capillary action formula. The structural morphology of paper after surface sizing was observed and analyzed with scanning electron microscope. The mechanism for enhancing strength was also discussed and analyzed.