New Hydrogel Condoms ‘More Like Human Skin'

WOLLONGONG, AUSTRALIA - Latex could be replaced as the primary material in condoms.
Researchers at the University of Wollongong in Australia who were awarded a grant from the Bill & Melissa Gates Foundation are furthering research into substances called tough hydrogels, which are currently used in medicine and robotics.

“We hope to deliver a condom that is safe and feels and looks better,” a UW release states. “It’s designed to feel more like human skin than latex rubber.”

The research team touts other benefits of hydrogel condoms, including invisibility and self-lubrication.
“That would eliminate problems with latex allergies and improper use of oil-based lubricants,” according to the release.

Dr. Sina Naficy, a polymer scientist working on the project, said the so-called “next generation condoms” could also be more environmentally friendly because the hydrogels are mostly made of water.
“Hydrogels can also be made to be biodegradable, which solves the problem of condom disposal,” according to the release........CLICK HERE to read the whole article

Use of Solubility Parameters in Solvent Based Adhesives

Manufacturer: We are manufacturing water based adhesives based on PVac and natural rubber latex. Recently we have decided into venture into solvent based adhesives due to the response to market requirement of our customers. We were advised to look into "solubility parameters" of both polymers we used and the available solvents to determine what solvents are best for what polymers.

What is "solubility parameters" anyway?

John Woon (Senior Latex Consultant): To cut the long story short, solubility parameter is a numerical estimate of the degree of interaction between materials (e.g. solvent with solvent or solvent with polymers), which indicates how good is the miscibility or solubility of the different materials when mixed together. Materials with similar values of "solubility parameter" are likely to be miscible e.g. a polymer with similar solubility parameter of its solvent would be easily dissolved in that solvent.This makes your life so much simpler when you want to choose a suitable solvent for your polymer such as polychloroprene and natural rubber.

To understand fully the chemistry/physics involved, one has to consider Van der Waals forces, cohesive energy density and heat of vaporization of the materials.



The theory behind solubility parameter was proposed by a renowned chemist and scientist, Dr. Joel Henry Hildebrand (November 16, 1881 – April 30, 1983) hence the term "Hildebrand solubility parameter" is often used.

Controlling of Baby Soothers Thickness with Heat Sensitized Latex

Manufacturer: We are manufacturing baby teats and soothers (pacifiers) with heat sensitized latex compound. We find controlling the product thickness of the soothers to be very difficult. We hope you can give us some practical tips to overcome this problem.

John Woon (Senior Latex Consultant): There are so many factors involved in this dipping process that could lead to inconsistent thickness of your products. Briefly, some of these factors are as follows:

1) Latex pH must  be closely controlled and monitored before and after the addition of the heat sensitizer.
2) Former temperature should be high enough to ensure good pick of latex but must be well controlled so that a latex dwell time of only a few seconds should suffice.
3) Latex temperature should be at around 20°C and must not vary for more than 1°C.
4) Prevulcanised latex offers better control of product thickness compared to post-vulcanisable latex compounds.

If you want I can prepare a detailed report for you.