关键词: 自乳化苯乙烯丙烯酸酯, 装饰原纸, 表面处理, 适印性, 吸收性

Abstract: 【Objective】Decorative paper, which was widely used in the surface finishing of wood-based panels, can not only protect the wood-based panels from wear, heat and contaminations, but also endow the products with excellent visual effects. With the development of wood-based panel industry and the related fields, more and more attention has been paid to the properties of decorative paper, which are determined by the properties of the decorative base paper directly. Among the performance indices of decorative base paper, the two key indices are printability and absorbability. The former affects the print quality and the latter affects the absorption of melamine in the production of decorative paper. In general, surface treatment is considered as an effective method to obtain excellent printability of decorative base paper, but weak absorbability of paper is also found in traditional manufacturing method. Thus, new types of surface-treatment agents are needed to develop.【Method】Styrene (St), butyl acrylate (BA), methyl methacrylate (MMA) were used as raw materials. Acrylic acid (AA) was introduced as the functional monomer. The latex was used in the surface-treatment of decorative base paper for good printability and absorbability. The influencing factors, such as the dosage of acrylic acid, the dosage of initiator, the mass ratio of hard monomer with soft monomer, were studied and the optimal conditions were achieved. Then, the products were characterized by scanning electron microscopy, microscopic infrared spectroscopy, laser particle size analysis, rotational viscometer and particle charge detection.【Result】The results showed that the excellent performance and good surface-treatment effect of self-emulsifying SAE were achieved when the reaction conditions were controlled as follows: 8wt% AA, 0.3wt% ammonium persulfate, mass ratio of styrene (St) to butyl acrylate (BA) 1.5:1. Under the optimal conditions, the latex particle size was around 130 nm. The latex viscosity was 20 mPa·s and the latex charge density was 0.7 mmol·L^-1. Compared with untreated paper, the printability of the decorative base paper was apparently improved and the absorbability of paper sheet was maintained. When the coating weight was 2 g·m^-2, the capillary rise was 19 mm·(10min)^-1. The surface strength was 1.1 m·s^-1 and the smoothness was 130s, which were better than the values of national standard GB/T 24989—2010. The surface-treated paper was covered by film partially and carboxyl was observed on the paper.【Conclusion】When acrylic acid, which has hydrophilic and reactive carboxyl, is introduced as the functional monomer for the preparation of SAE, the self-made surface treatment agent can simultaneously meet two demands: improving the surface property and printability of paper, and maintaining the absorbability of paper. Introducing self-emulsifying styrene acrylate emulsion as surface-treatment agent is an effective method for improving the quality of decorative base paper. In the future study, the type, dosage and adding method of functional monomer, and the same role as AA in this paper, should be researched emphatically.

Key words: self-emulsifying styrene acrylate, decorative base paper, surface-treatment, printability, absorbability