-----------------

JW Latex Consultants (and Rubber Consultants,乳胶顾问) offer solutions to your problems in Natural Rubber latex and Synthetic Rubber latex processing and the manufacturing of latex products (condoms, catheters, medical gloves, baby teats and soothers, toy balloons etc) Quick answers through e-mails are possible at reasonable cost.

You Are Visitor Number:

counter
Expedia Promotional Codes

__________________________

This Site Is Best Viewed With Mozilla Firefox Browser. If You Are Viewing With Internet Explorer, It Is Advisable to Switch to Mozilla Firefox By Going to This Link -> http://www.mozilla.org/en-US/firefox/new/

It Is Free to Download

__________________________

Send Your Enquiry and Orders To: woonsungliang@yahoo.com.sg

Problem Solving Through E-Mails with John Woon Latex Consultants Is Possible
可以通过电子邮件与JW乳胶顾问来解决问题

__________________________

Please kindly donate to support the maintenance of this site. We'd appreciate it very much.

__________________________

__________________________________________________________________________

Wednesday, January 04, 2012

Doubts About Air Bubbles in Natural Rubber Latex

Student:  I'm actually a student of University Malaya. Currently, I am studying the cause of bubble formation in natural rubber latex and attempting to control and diminish it.

Referring to journals, bubble forms when gas is introduced into solution which containing either surfactant or protein.

Below are some doubts from me:

1) What are the surfactant that usually applied in latex processing? Is that Tween 80, Trixton 100?. 2) Hevein and Ovalbumin are the protein in the natural rubber latex ? 3) Besides Biuret test, any other simpler to test the protein level? As I know, oil based antifoam is usually used to control bubble. However, is there any other ways?

Thank you. Hope to hear from you soon.


John Woon (Senior Latex Consultant): The followings are my answers to your questions:

1) The surfactant usually used by both the latex producers and latex products manufacturers is ammonium laurate. Occasionally, latex products manufacturers also uses potassium laurate, oleate and other anionic surfactants such as sodium lauryl sulphate.

Non-ionic surfactants such as Tween 80, Trixton 100 are seldom added into the latex unless one encounters a severe loss of chemical stability.

2) Proteins in latex are found on both the rubber particles and the aqueous phase of the latex. These are mainly the alpha-globulin and hevein.

To measure the total protein level, you could determine the Nitrogen content using the Kjedahl method and multiply the result by a factor of 6.25.

For water extractable protein, you can use the so-called Modified Lowry method as that used by the medical glove industry, namely, ASTM D5712 - 10 (Standard Test Method for Analysis of Aqueous Extractable Protein in Natural Rubber and Its Products Using the Modified Lowry Method)

3) Although foaming is due to reduced surface tension as a result of the addition of surfactants, there are other factors that could lead to foaming tendency. Pure liquids do not foam while a solution and a mixture often do.Hence, you have to also study the effect of other ingredients in the latex besides the surfactants.

Not all antifoam agents are oil based. Carefully selected non-ionic surfactants with the right HLB ratio could act as an effective anti-foaming agent.        

                                          

0 Comments:

Post a Comment

<< Home

__________________________

What has the bouncing ball to do with tyres?

Latex Gloves Educational Articles from the Malaysian Rubber Export Promotion Council

How do you select your medical gloves?

Rubber Chemicals: Carcinogenicity, Mutagenicity, Clastogenicity.

Why is Compression Set measurement important?

Assessment of Latex Stability

Joule Effect

Poor Flocking Quality Of Household Gloves

Creaming of Latex

What is Vulcanization?

History of Latex Dipped Products

Applications of Prevulcanized Latex

Defoamer Creating Havoc in Glove Factory

Problems With Milling Rubber Chemicals

Medical Gloves From Guayule Latex

Introduction to SMG Gloves

 

 

Click on The Following Links to Read More Articles:

[Advantages of Vulcanization] [Applications of PV Latex] [Bacteria and Latex] [Chemical Toxicity] [Cross-Linking Density] [Biodegradability] [Black Articles] [Blooming] [Bouncing Ball] [Compression Set] [Condoms] [Creaming] [Defoamer] [FDA] [Fatty Acid Soaps] [Flame Retardant] [Flocking] [Food Packaging] [Glove Demand] [Glove Selection] [Guayule Latex] [History of Gloves] [Joul Effect] [Latex Stability] [Latex Thread] [Milling Problem] [MREPC Articles] [Nano Polymer Particles] [Nano ZnO] [Polychloroprene] [REACH] [SMG] [Storage Hardening] [Vulcanization] [Vytex] [Yulex]

Disclaimer:
The information and data contained in this site are believed to be accurate and reliable. However it is the responsibility of the visitors and readers to satisfy themselves that the information is workable under their own processing conditions. Hence the owners of this site make no warranties concerning the suitability of the information given in this site.

__________________________