Training Courses by John Woon Latex Consultants

Manufacturer: We understand you also conduct on-site training for latex factories. Can you let us know the content of your training materials?

John Woon (Senior Latex Consultant): I offer quite a varied training courses to engineers, chemists, technologists and technicians engaged in the latex and latex products industries. Among others, the following are some examples of the subjects:

1) NR latex properties (Including latex stability, importance of process controls by latex producers, how to overcome destabilization problems such coagulum, viscosity, etc)
2) Dipping Technology (Discussion covers all stages of dipping process for gloves, condoms, toy balloons, etc)
3) Faults and defect of gloves, their causes and recommended remedial actions
4) Antigen, allergen, protein
5) Milling of rubber chemicals (choice of dispersants, mechanism of grinding and selection of milling machines)
6) Nitrosamine in Rubber Products – How to overcome them?
7) Prevulcanised latex and Post-vulcanisable latex (Pros and Cons)
8) Stage-Gate Process For New Product Success (An R&D System)
9) Nitrile Latex
10) Polychloroprene Rubber
11) Adhesive technology
12) 6-Hat Thinking

For some of the PowerPoint slides I use, please visit this site  http://www.slideshare.net/johnwoon/john-woons-training-slides

How to Control Latex Creaming

Manufacturer: Lately we've been encountering uneven latex pick up and we have been advised that this could be due to latex creaming. What is latex creaming and what we could do to prevent it?


John Woon (Senior Latex and Rubber Consultant): The Specific Gravity (SG) of rubber is about 9.02 while that of the serum (water phase) is about 1.02. This means the rubber particles are lighter than the serum hence there is always a tendency of the rubber particles to rise to the top of the container, a process which is commonly known as “creaming”. 

If the latex is allowed to stand without agitation, over time (especially when exposed to elevated temperatures) a top creamy layer with high TSC and DRC would be formed. Fortunately this “cream” is readily re-dispersed into the other part of the latex with some stirring. Therefore, to minimize the incidence of creaming, latex in storage tanks (or any other containers including your compounding tanks) should be agitated periodically, for instance, once per day for 30 minutes at slow to medium speed. 

 For your latex dip tank, proper agitation must be attained to ensure maximum latex homogeneity without too much turbulence to cause the formation of air bubbles.