ASTM offers rubber testing course

W. Conshohocken, PA -— "Rubber Testing: Selecting, Performing, and Interpreting ASTM Rubber Test Methods," a new Technical and Professional Training course sponsored by ASTM International, focuses on the most common rubber test methods that are used in the rubber industry today. It discusses the nature of the tests, why the tests are performed, interpretation of test results and how this information can be used to improve rubber fabrication.

This class is designed for rubber technologists and rubber chemists; compounders; process engineers, laboratory managers, supervisors and technicians; quality assurance managers and engineers, shop foremen, technical sales people, rubber producers and users; or anyone with a need to understand these commonly used ASTM test methods.

This course will be offered April 16-17, 2008, and Sept. 24-25, 2008, at the University of Akron Polymer Training Center in Akron, Ohio; and Dec. 11-12, 2008, in Miami, Fla. The Miami class will be held immediately following the semiannual meeting of ASTM Committee D11 on Rubber. Class participants are invited to come early and attend the D11 meetings. For further information, including cost, registration, hotel reservations, vist the ASTM home page at www.astm.org.

You are at the site for answers and solutions to all your problems in natural rubber latex processing and manufacturing of industrial, household and medical gloves, condoms, catheters, baby teats and baby pacifiers, toy balloons, latex foam products, latex threads etc.

Dow Reichhold increases price for nitrile latex for glove manufacturing

Monday, November 5, 2007
Research Triangle Park, NC -- Dow Reichhold Specialty Latex has announced a worldwide price increase for nitrile latex used in the manufacture of gloves. Effective January 1, 2008, the price of nitrile butadiene (NB) latex for glove manufacturing will increase from three to five percent (3-5%) worldwide. The company expects continued escalation in the costs of raw materials, energy and logistics. The company said it is raising prices on its glove polymers to maintain margins that allow for reinvestment.

You are at the site for answers and solutions to all your problems in natural rubber latex processing and manufacturing of industrial, household and medical gloves, condoms, catheters, baby teats and baby pacifiers, toy balloons, latex foam products, latex threads etc.

Proteins vs Lipids in Natural Rubber Latex

Manufacturer: Can you explain the roles played by both the naturally occurring proteins and fatty materials in natural rubber latex in terms of the latex colloidal properties? Why can't the latex stability sustain over a long period of storage time?

JohnWoon: Freshly obtained latex from natural rubber trees (Hevea Brasiliensis) contains mainly proteins (including phosphoproteins) and lipids (including phospholipids) at the rubber and water (serum) interface.

In the cause of latex production in factories, ammonia is added as a preservative. In the presence of ammonia, the hydrolysis of both protein and lipids (phospholipids) takes place with the latter at a faster rate than the former. The hydrolysis of phospholipids takes about 3 to 5 weeks with the gradual resultant formation of fatty acid soaps. Hence you also see a gradual increase in the mechanical stability. On the other hand, the hydrolysis of proteins, while taking a longer time, would lead to the formation of smaller polypeptides and amino acids (which tend to destabilize latex).

This accounts for the initial build-up of latex colloidal stability followed by the eventual loss of stability with time. Some studies reveal that the artificial replacement of the rubber-water-interface proteins with more surface active materials followed by centrifugation could eliminate or reduce the level of the destructive amino acids.

You are at the site for answers and solutions to all your problems in natural rubber latex processing and manufacturing of industrial, household and medical gloves, condoms, catheters, baby teats and baby pacifiers, toy balloons, latex foam products, latex threads etc.