cashew nut shell resin instead of epoxy resin ?

[mikakun2012]

Hello,

has any one heard of this ?

http://www.arcoy.com/arcashew.htm

i believe many other Indian companies are commercialising similar products

Could it be a cleaner (pollution/health wise) and cheaper alternative to epoxy resin?

It sounds like to me but I don't know, and I have been searching around & haven't found yet a reason against.

thanks for your lights

(I'm a full newbie willing to build a sailboat in India and looking on the local market to source the materials)

[lewisboats]

"Tough" and "Elastic" are not necessarily something I want in a glue bonding parts together in a structure that is subject to twisting and heaving motions. It seems the joints would work themselves apart. Note the applications in the literature...brick mortar, Flooring, in general stuff that stays put and doesn't move around. It might be OK as a barrier coat...some testing would be in order. What is it's UV resistance?

[PAR]

The first thing I would question is the controls in place in Indian industry, to insure suitability and compatibility with a number of issues. This isn't a dig at India, but an observation of what we've been taking for granted in western nations for decades, which is required testing for several consideration in new product uses and applications. These controls in some areas of the world (India included) are scant if non-exsistant, which can lead to untold problems.

[mikakun2012]

It might be OK as a barrier coat...some testing would be in order. What is it's UV resistance?

Yes I was thinking about that. What test would you do ?
I have no idea about UV resistance, i believe epoxy resin is not uv resistant but i have no idea which component of the resin is culprit

found this

Cashew Nut Shell Liquid, Specifications :

Specific Gravity 300 C : 0.950 - 0.970cnslbeaker

Viscosity 300 C in centipoises : 200 max.

Moisture by weight : 1.0

Matter insoluble in toluene weight :1.0

Loss in weight on heating : 2

Ash % by weight : 1.0

Iodine Value : (min.)

a) Wij’s Method : 250

b) catalytic method : 375

Polymerization:

a) Time in Minutes : 4

from http://www.kancoindia.com/ they are selling the bare oil with which they say you can make

CNSL has innumerable applications, such as friction linings, paints, laminating resins, rubber compounding resins, cashew cements, polyurethane based polymers, surfactants, epoxy resins, foundry chemicals, and intermediates for chemical industry. It offers much scope and varied opportunities for the development of other tailor-made polymers.

... with good chemistry skills but maybe not that complicate ?

PAR I know what you mean I live in India, however india has changed, if you don't know what i mean just check out the new delhi airport...or the new delhi subway... they want it like in the west now + they have to face very tough chinese competition...the've upgrade/are upgrading everything & they're proud of it. And anyway, in India everything is there including QUALITY, but you have to dig for it hard otherwise you will be given the cheap, unreliable thing.

(in fact it is because india is becoming like the west that we want to build a live aboard and sail away )

[mikakun2012]

http://www.reinforcedplastics.com/vi...-nutshell-oil/

Composite Technical Services LLC (CTS), Kettering, Ohio, USA, along with its partner Cimteclab Srl, Trieste, Italy, has pioneered a line of novolac resins called Novocard™ XFN to help the composites industry develop more sustainable products. But the material’s unique chemical structure also enhances performance properties, giving customers the value-adds they need to remain competitive.

[Herman]

I have a couple of "green" alternatives to epoxy and polyester on the shelf.

Price is not cheaper than "grey" stuff, but you would not be surprised.

Health issues usually are the same, as the curing system is the same as normal epoxy, with its associated health hazards.

As for quality, it usually is quite similar.

If you let go the curing chemistry, you get other materials, with other properties. We now have a 100% green material, biobased (Combiolite), but these products sometimes can do wacky things. Like shrinking 5% or more, or only cure at 80 degrees C. Good for a number of products, but difficult for boats.

Most popular here are "Greenpoxy" from Sicomin, and a 50% green infusable polyester from Polynt. These products work really well, and give predictable and good results. Especially the polyester is very easy to work with.

[mikakun2012]

thanks for your informative post

I conclude the advantage of using cashew oil instead of petrol oil is the last one standing !

but when you are concerned by the diktat of the petrol lobby over the range of our choices in everyday life or the GOM type of situation petrol industry creates more than often, that still makes a big difference

[mydauphin]

The hear the cashew glue taste better than epoxy...