Fraunhofer Researchers Develop Natural Rubber from Dandelions

Approximately 40,000 products of everyday life contain natural rubber. It’s the material that provides extreme elasticity, tensile strength and low-temperature flexibility in products from mattresses and gloves to adhesive tape and tires. As yet, it has no artificial replacement. However, researchers from the Fraunhofer Institute for Molecular Biology and Applied Ecology IME were able to identify a cost-effective and eco-friendly alternative to the natural rubber tree: the dandelion.....CLICK HERE to read the whole article.

Latex Stability Problem Due to Addition of Filler

Manufacturer: We are adding filler to our latex compounds to reduce cost while increasing modulus. However, every time we do this we encounter a lot of problems due to a drop  in latex stability.

 
John Woon (Senior Latex Consultant): You did not tell me your stabilizing system and how much stabilizer you are using. The problem you encountered is due to the fact that the stabilizers of the rubber particles are being "robbed" by the filler.

As a general rule, the level of the stabilizer (i.e.surfactant) added should be proportional to the quantity of filler added. Also, the level of stabilizer added to the filler that is in the form of a aqueous dispersion (or slurry) is lesser compared to the case when the filler is added as dry powder.

You should also take note that the lower the particle size of the filler, the higher is the level of the surfactant required.

Sometimes a blend of more than one surfactant works better than when only a single surfactant is used.

Latex Thread Manufacturing - General Advise

Manufacturer: We are medium sized latex thread manufacturer just beginning production. We're still struggling to get optimization of the production process. A general comment from you would be highly appreciated.

John Woon (Senior Latex Consultant): "A general comment" is far from adequate as the latex thread extrusion is a complex process.

Anyway, here's my general advise:

1) The particle size of your compounding chemicals should be free from coarse particles especially for thread of smaller diameters. It should be below 3 micron.

2) The latex compound must be well matured at room temperature for a number of days depending on your cure recipe. This must then be followed by high pressure homogenizing,  deaeration under vacuum and filtered before use.

3) Dry and cure at between 15 to 20 minutes at 125°C to 130°C. You can also try a shorter cure at higher temperature followed by post curing at lower temperature at about 70°C.

If you need my full report on the "Manufacturing of Latex Thread", please let me know.