Starch is a polysaccharide: basically a sequence of polymer molecules “glued together” by their carbon atoms. Also in these molecules are oxygen atoms, which bind to hydrogen to form one of the simplest structures in organic chemistry, called a hydroxyl group. Ethers are also molecular structures called alkyl or aryl groups, which bind to oxygen atoms in the starch to form a starch ether.

The structure of a starch ether is “hydrophilic”, meaning it attracts and retains water. This is how starch ethers create benefits across a range of industrial products: keeping water in a compound lets manufacturers control how a mixture thickens, emulsifies, and stays stable in a range of conditions.

As organic compounds, starch ethers are found in many business and consumer products, from food to paper to constructional materials. In the building and construction sector, they’re often used in surfacing and adhesion products. These include cementitious dry-mix mortars such as tile adhesive, stucco render, and EIFS, and dry-mix gypsum mortars for smoothing, finishing, and filling.

Starch ethers are flexible and available in a range of formulations suited to many use cases. Dry-mix materials are used all over the world in many different conditions; adding starch ethers to a dry-mix mortar product lets producers control a mixture’s smoothing ability, reducing the tendency of adhesives to sag and slip, make it easier to work with over large or difficult surface areas, and extend open time.

Starch ethers can be added at source in the factory, or added to ready-to-use products on construction sites to improve their performance characteristics. A small dosage into a dry mortar formulation results in a significant performance benefit.

While starch ethers can replace cellulose ethers in some applications, it’s often more advantageous for the two to work together. In short, a starch ether and a cellulose ether have different functions, but they work synergistically together to impart very beneficial improvements to a dry mortar formulation.
The primary function of a cellulose ether is to help retain water in a formulation to support complete of the primary binder (cement or gypsum). A starch ether’s main function is to improve workability, reduce slip and sag, support water retention, reduce stickiness and support with open times. Adding small volumes of starch ethers lets producers control rheology (the “feel” of a product) with high precision – for example, making a mixture more workable and pumpable without making it thicker.
Starch ethers impart a buttery feel that is much appreciated by professionals.

Both starch and cellulose are organic compounds called polysaccharides, and when turned into ethers their main property is water retention. But since their molecular structures once etherified are different, the compounds have different properties – so mixing the two can give a wider range of advantages, from viscosity to workability, that each compound is less effective for when used alone.

Starch ethers can come from many sources, but Avebe’s starch ethers are derived from natural starch in potatoes, a renewable crop – so there’s no deforestation or other environmental damage in the production chain. Furthermore, the potatoes used aren’t for human consumption, so there’s no impact on the food supply.

Starch ethers are flexible compounds with many applications across the building sector, but each application has its own requirements. A smooth finish is vital for skimcoat plaster, for example, but less so for rough stucco, or coatings that will be covered by further surfacing or tiling. That’s why there are many formulations of starch ethers in use today – because each gives a different combination of advantages for its use case.

Different application and different formulation have different requirements. Thus, Avebe has created a range of products with different degrees of various modifications to cater to the needs of the market. Avebe are the originator of the Starch Ether Typing, where the consistency curve profile varies with dosage.

Starch ethers bring benefits at low concentrations. A: Avebe Starch ethers are highly efficient additives and deliver significant formulation benefits at very low doses. Dosages vary according to the primary binder used, the formulation and the end application. Typical starting dosage is approximately 0.1% of cellulose ether.

Avebe is at heart a farming collective: a group of agricultural professionals with an interest in finding new applications and use cases for the products it grows. Many sustainable and renewable agricultural products – like potatoes – contain organic compounds that can add value to many industrial products while offering environmental benefits too. We have the knowledge to help you make the right selection and guide you on the usage of starch ethers in your formulations.

Professional opinions about starch ethers are positive and widespread. Tilers value the way they reduce sag or slip; plasterers like the improved workability and open time they add to dry mix mortar; large construction sites gain advantage from easier pumpability that makes projects move faster with less rework. And with starch ether additives for ready-for-use available, building trade professionals can also “dial in” the performance characteristics – such as thickness and smoothness – that are right for their job.

Around the world, many jurisdictions (like the EU) are requiring ever-stricter sustainability standards for industrial businesses – with the construction sector among the largest producers of CO2. Starch ethers are helping large organizations control their emissions along the value chain and prove their environmental credentials to shareholders.

Around the world, many jurisdictions (like the EU) are requiring ever-stricter sustainability standards for industrial businesses – with the construction sector among the largest producers of CO2. Starch ethers are helping large organizations control their emissions along the value chain and prove their environmental credentials to shareholders.

As organic products derived from renewable sources, starch ethers are often a greener choice than synthetic ethers (which do not have sustainably source materials) or cellulose ethers (which often contribute to deforestation). Avebe’s starch ethers, derived from potato starch, are both renewable and low-impact with a transparent value chain.

A network of distributors supports and stock Avebe Starch ethers globally. These distributors are in turn supported by Country Managers and the Technical Team at Avebe. Just write in to us and you will get the help you need in using Avebe’s Starch Ethers.