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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.

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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

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Thursday, June 15, 2006

What are the applications of prevulcanised latex ?

Student:You had mentioned the advantages of using prevulcanised latex. Can you please briefly describ the products that are being produced commercially using prevulcanised latex?

JohnWoon:Yes, I've discussed the various advantages of prevulcanised latex (PV) in my earlier posting. Here I would like to just mention again in summary as follows:
1) Simple to use
2) Long shelf life
3) Low residual chemicals
4) Low toxicity
5) Maturation and vulcanization not required
6) Better efficiency in leaching
7) One formulation for all seasons

As regards the possible uses of PV, the list could be quite extensive.The following list shows only some important examples of the applications. I'm also including the the basic requirement, recommended types of prevulcanised latex and choice of manufacturing methods.

1) Medical Gloves and Electrian Gloves
Basic requirements: Good tactility and elasticity, low TypeIV Allergic Reaction.

Types of PV : Medium to high modulus.

Method : Coagulant dipping - Single and Multiple.

2) Catheters
Basic requirement: Low toxicity, good balloon symmetry for Foley catheters, good adhesion between dips.

Types of PV : Medium to high modulus.

Method : Multiple coagulant dipping.

3) Toy Balloons
Basic requirement: Low nitrosamine and low nitrosatables, easy to inflate, low bursting rate during printing, good balloon symmetry and sheen.

Types of PV : Low modulus, low nitrosamine.

Method : Single coagulant dipping.

4) Baby Teats and Soothers/Pacifiers
Basic requirement : Low nitrosamine and low nitrosatables, good clarity, good ageing resistance to boiling.

Types of PV : Medium modulus, low nitrosamine, high clarity.

Method : Single coagulant dipping and heat sensitized dipping.

5) Marking Rings
Basic requirement : High tensile strength, high elasticity, low tension set, good ageing resistance.

Type of PV : Medium to high modulus.

Method : Single coagulant dipping.

6) Condoms
Basic requirement : High bursting pressure and volume, high clarity, low TypeIV Allergic Reaction, low toxicity.

Type of PV : High modulus.

Method : Straight double dipping (i.e. with no coagulant)

7) Breathing Bags and Masks (for administering of anesthetic)
Basic requirement : Good elasticity, low toxicity, good fatigue resistance, good ozone resistance.

Type of PV : Medium to high modulus.

Method : Single or double coagulant dipping.

8) Can Sealants
Basic requirement : Low residual chemicals, low toxicity.

Type of PV : Medium to high modulus.

Method : Casting and injecting.

9) Adhesives
Basic requirement : Quick grab, good cohesion and adhesion strength.

Type of PV : Low to high modulus.

Method : Roller coating and brushing.

10) Flooring
Basic requirement : Good outdoor ageing resistance, good bond strength to rubber crumbs.

Type of PV : Medium to high modulus with excellent adhesion to rubber substrate.

Method : Trowelling.

11) Rubber Sheeting (for garments and exercise bands)
Basic requirement : Good elasticity, soft silky feel, latex compound should be easily heat sensitized.

Type of PV : Low to high modulus with good heat sensitizing property.

Method : Coagulant dipping or continuous heat sensitizing casting.


Conclusion

Although both prevulcanised latex and post-vulcanisable latex compound are widely used for the manufacturing of a variety of latex products, the former offers many manufacturers a ready-to-use latex compound with ease of processing which requires simpler process controls with added comparative advantages of low toxicity and long shelf life. As a result, prevulcanised latex has been very popular for the manufacturing of medical devices such as medical gloves, condoms, catheters, baby teats and pacifiers.



You are at the site for answers and solutions to all your problems in natural rubber latex processing and manufacturing of medical gloves, condoms, catheters,babay teats and pacfiers.

Do we need new regulations for food contact nanomaterials?



Manufacturer:We understand that some polymer packaging materials for food are incorporated with nano-sized additives. Are these new products really safe? What about food handling gloves with similar additives? Are existing regulations adequate to control these materials?

JohnWoon:Everybody knows that nanomaterials industry is fast-growing and is currently working mostly within the scope of existing national regulations. We also know that such regulations have been developed for traditional materials and not nanomaterials.

Despite chemical similarity, nanoparticles could behave quite differently from their regular counterparts due to their very small size, for instance, nano-sized Zinc oxide is expected to behave differently from the normal Zinc oxide i.e. they must therefore be classified as new materials and treated as such.

In short, many experts believe that the existing national or international standards and regulations might not be adequate to control the new materials.

I understand that the UK government is in the process of testing PET bottles and other packaging materials incorporated with nanoclay to improve the impact resistance or nano-sized antibacterial silver particle to prevent and control bacterial growth.

Some of the tests include the assessing of the migrating behavior of these additives and the determination of how leachable they are. I hope they are also studying the toxicity aspect as well.

Critics of nanotechnology are expressing the potential toxicity of these nanosubstances that could adversely affect the stability of cell membranes or disturb the immune system when inhaled, digested or absorbed through the skin. The concern is that by being reduced to the nano-scale, materials become more reactive and therefore potentially more toxic.

The same argument should be applicable to similarly compounded latex products coming in contact with food such as food handling gloves.



You are at the site for answers and solutions to all your problems in latex and rubber technology.

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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.

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