Starch Ethers Used in Construction Chemicals

  In recent years, parallel to the growth trend in the construction sector in our country, product diversity in building chemicals production has been increasing day by day. Accordingly, the main product groups used in building chemicals are: •Binders; gypsum, cement, clay, etc., •Aggregates; quartz, silica, calcium carbonate, •Thickeners; polymers, natural thickeners (cellulose, starch...), synthetic thickeners (polyacrylamide, polyacrylate, polyurethane), •Water and process auxiliary chemicals. One of these chemicals is starch, a natural thickener (rheology modifier). Looking at the sectors where starch is used: •Food industry / Baby food products, •Non-GMO corn-based products / Organic products, •Paper industry / Textile industry, •Building chemicals / Cosmetics industry, •Pharmaceutical sector / Mineral oil industry. Agrana, an Austrian company, is one of the sector's leading starch ether manufacturers and represents our company. It is an internationally market-oriented company that produces products for many industrial sectors. Research activities are conducted in the starch technology department of the Agrana Research Innovation Center (ARIC). The agricultural raw materials from which starch is obtained are wheat, corn and potatoes. According to statistics, the percentage distribution of raw materials processed in Europe for starch production is; 47% corn, 13.3% potatoes, 40% wheat, totaling approximately 10 million tons. The raw material distribution of Agrana's starch ethers is; 74% corn starch, 6% potato starch, 13% wheat starch, 7% waxy corn starch. Agrana produces starch for food and non-food sectors, with building chemicals being the leading sector. The applications in building chemicals include; gypsum-based drywall, putty, cement-based tile adhesives, mortars, emulsion-based paints and concrete. In the building chemicals sector, potato-based starch ether is the most preferred due to its high performance, increasing viscosity, and particularly preventing sagging in tile and ceramic adhesives by adjusting mortar consistency. They also improve workability in mortars. They are used together with cellulose ethers. By adding cellulose ether at 25% to the final product formula, it helps reduce cellulose ether usage as well. In plasters and insulation coating adhesives, they are preferred for their high effectiveness in preventing flow and sagging. Looking at the composition of potato-based starch ether, it contains 76% water, 18% starch, 2% protein, 0.5% sugar, 0.7% fiber. The starch portion is composed of two molecular compounds called amylose and amylopectin. While amylose is linear, amylopectin has a branched chemical structure. Amylose helps with gelation, viscosity and consistency increase, while amylopectin provides stability. In potato-based starch ether, there is approximately 30% amylose and 70% amylopectin. Agrana's Amitrolit® series starch ethers are widely preferred in building chemicals products due to their high performance. They strengthen the consistency of hydraulic binder (cement, gypsum, lime) based products through their segregating effect on the rheological behavior of the binding matrix in water. With appropriate applications of Amitrolit® varieties, flow and sagging are significantly prevented in products like tile adhesives and mortars, while workability (open time, ease of application) can be optimized with proper dosing. Amitrolit® products are compatible with many aggregates and additive chemicals. They increase the effect of additive chemicals, making it possible to use them in smaller quantities. Amitrolit® products show less sensitivity to calcium ions at high pH levels compared to other starch ether products. Recommended types for cement-based building materials are; Amitrolit® 8850, Amitrolit® 8860, Amitrolit® 8872, Amitrolit® 8873, Amitrolit® 8873c, Amitrolit® 8882, Amitrolit® 8869. Application areas include mortars, plasters, tile and ceramic adhesives (C1 and C2 according to EN 12004), external facade insulation systems, etc. Recommended types for gypsum-based building materials are; Amitrolit® 8850, Amitrolit® 8873, Amitrolit® 8873c, Amitrolit® 8882. Application areas include mortars and adhesives, plasters, machine plasters, sealant putty.

Summarizing the advantages of starch ether below;

•Rheology adjustment, •Workability, •Flow-slip resistance, •Water retention, •Setting delay. As Boysan Boya San. ve Tic. A.Ş., with our 49 years of technical and commercial experience, we are pleased to present Agrana's Amitrolit® starch ether products to the market in Turkey and the Turkic Republics.