In order to achieve the desired hardness and effect of products made of molded paper pulp, additives are generally added. The following are five additives that are commonly used in the production of molded paper pulp.
1. Enhancer. To improve the strength of pulp products, the products added with the reinforcing agent can increase the hardness by 2-3 times which can help the products obtain the tensile, compressive and torsional resistance.
2. Water repellent. Add a water repellent to the molded paper pulp to increase the water repellency of the product. The additive is mainly used to improve the solidification quality of pulp as a model product, reduce the surface tension, fill the internal voids of the product, and play a waterproof role.
3. Retention aid. The function of retention aids is to increase the retention of fines, fillers and pigments in paper to improve quality and reducing costs of molded paper pulp.
4. Preservatives. Its function is to ensure that the molded paper pulp is not moldy, not rotten, and the paper is not eaten by insects, preventing parasites.
5. Oil repellent. Adding 0.5%-0.8% of oil-repellent can effectively improve the oil-repellent effect of products made by molded paper pulp.