Make Guar Gum Slime

Guar gum is a natural polymer found in guar seeds. It is a legume cultivated in India as livestock feed; however, it is also used as food additive and can be found in health food stores.

Like many other polyalcohols, the long molecules of guar gum can be cross-linked to form slimy/elastic or rubbery substances.

Those of you who like this experiment can order a slime science kit that contain guar gum and other chemicals you will need for your slime experiments. With the chemicals you recreive in a kit, you can make many new and interesting products such as soft slime, Flip-Flop Slime, Power Putty, Glooze, Wiggly Wonder.
More importantly you will learn how you may modify the properties of different substance including their hardness, melting temperature and elasticity.

It is exciting for students to see how two liquids can mix and form a slimy or rubbery substance.



Curiosity often overwhelms those who see an unrecognizable substance. “What is it?” they wonder, “What can it be?”

Capture your students’ attention with this “goopy” slime recipe.


• Polymers, polymerization


  • Guar gum, 2 g

  • 10-mL Graduated Cylinder (or one table spoon measuring spoon)

  • Sodium borate solution, 4%, Na2B4O7, 10 mL or one table spoon

  • 250-mL Graduated Cylinder or one measuring cup

  • Water, distilled or deionized, 200 mL or one cup

  • Food coloring (optional), 1–2 drops

  • Stirring rod (or a regular spoon)

Safety Precautions

Slime is generally considered nonhazardous; however, it should not be ingested and should only be used in the manner intended. It is not recommended that students be allowed to take slime home. Slime will easily stain clothing, upholstery, and wood surfaces. With food coloring added, it will stain these surfaces and skin even more readily. Wear chemical splash goggles, chemical-resistant gloves, and a chemical-resistant apron. Please review current Material Safety Data Sheets for additional safety, handling, and disposal information.


1. Add 250 mL (or one cup) of distilled or deionized water to the small plastic cup. If desired, add a few drops of food coloring to the water and stir.

2. Slowly and with constant stirring, add 2 g of guar gum to the water. Note: If the guar gum is added too quickly, it will form large, undesirable clumps. Stir until dissolved. The mixture will thicken slightly within 1–2 minutes.

3. Add 10 mL (or one table spoon) of 4% sodium borate solution. Stir. The mixture should gel in 1–2 minutes.


Slime can be disposed of with regular household garbage unless otherwise is regulated by your local, state or federal government. review all federal, state and local regulations that may apply, before proceeding.


• Try using distilled or deionized water. The ions present in tap water may interfere with the polymerization reaction, causing the slime to turn watery after only an hour or two. Slime made with distilled or deionized water will retain its properties and consistency for several days.

• Store the slime in an airtight container or bag to prevent it from drying out.


Guar gum, a natural polymer with a molecular weight of about 220,000 g/mole, is made from the ground endosperms of Cyamopsis tetragonolobus, a legume cultivated in India as livestock feed. Guar gum has 5–8 times the thickening power of starch and is commonly used as a binding or thickening agent in foods and cosmetics.

Guar gum is a long-chain polyalcohol with 1,2-diol groupings capable of complexation with the borate ion, B(OH)4–. The structures given below are oversimplified, but may help to visualize the network complex as it extends in three dimensions.


In addition to forming complexes with the borate ion, the interaction of long-chain polyalcohols, such as guar gum, with the borate ion leads to cross-linking of different polymer chains, or sometimes part of the same chain, in such a way that a three-dimensional network of connected chains is formed. When the concentration of cross-linked chains is high, solvent is immobilized within the network and a semisolid gel results. Because the borate ion can bond with four alcohol groups it is particularly effective in creating three-dimensional gel networks from gums such as guar gum.

Other examples of networks and gels are rubber cement, gelatin, fruit jellies, agar, and yogurt.

After you make your slime, you may place it in a bag for future use or display at the science fair. A plastic bag can keep your slime fresh and protect it from drying out.

Go Back to the Slime Home Page


You can order a Kit now

(Check price and availability)

Join science project dot com for information and support with your science project.