Gypsum wallboard, also known as drywall or plasterboard, is a type of building material used in construction for creating interior walls and ceilings. It is made from a gypsum core sandwiched between two sheets of paper or other materials. The core is made from gypsum, which is a soft sulfate mineral composed of calcium sulfate dihydrate. Gypsum wallboard is popular because it is relatively inexpensive, easy to install, fire-resistant, and has good soundproofing qualities. It is commonly used in residential and commercial construction projects.
Modified tapioca starch can play multiple roles in gypsum wallboard production, such as a paper adhesive and a core strength improver. As a paper adhesive, modified tapioca starches have various viscosity ranges that can match with the gypsum board operation temperature, providing good migration of starch molecules resulting in good adhesion between the gypsum core and paper liner. This improves the overall strength and durability of the board.
Modified tapioca starch can also act as a core strength improver by enhancing the strength of the gypsum crystals. This leads to increased flexural strength and nail pull resistance for lightweight gypsum board, which is a desirable property in the construction industry.
Furthermore, modified tapioca starch can also be used as a binder in the production of joint compound used for finishing gypsum wallboard surfaces. It improves the workability of the compound, providing better adhesion and reduced shrinkage, resulting in a smoother and more durable surface finish.