133 Polymers from Renewable Resources, Vol. 4, No. 3, 2013
Technical Analysis of Euphorbia caducifolia Haines Latex of South-East Asian Origin - Part I
Technical Analysis of Euphorbia
caducifolia Haines Latex of South-East
Asian Origin - Part I
Sanjay K. Bhattacharyya, Saptarshi Kar, Sugata Chakraborty, Saikat
Dasgupta, Rabindra Mukhopadhyay and Abhijit Bandyopadhyay
1*
Hari Shankar Singhania Elastomer and Tyre Research Institute (HASETRI), Jaykaygram,
P.O.Tyre Factory, Dist. Rajsamand, Pin- 313342, Rajasthan, India
1
Department of Polymer Science and Technology, University of Calcutta, 92, A.P.C.
Road, Calcutta-700009, India
Received: 14 March 2013, Accepted: 17 May 2013
SUMMARY
Identification and characterization of the latex from Euphorbia caducifolia Haines
has been thoroughly described in this article. The average total solid content
(TSC) of the latex was 27% and pH was found to vary between 6 to 7. About
70% by weight of the whole coagulum (Cog) was found soluble in toluene; rest
was insoluble. Toluene soluble portion (TE) was mainly composed of terpenes
and terpenoids of three different molecular weights; the lowest molecular weight
fraction being the dominant (82%) one. Presence of about 8% natural rubber
(NR, a polyterpene), mostly of cis configuration, was also identified from the
composition analysis of that portion. Due to dominant low molecular weight
mass, it was tackier as compared to Cog portion when manually felt. Thermal
characterization showed a low temperature melting behavior (starting at 70°C for
Cog and at 104°C for TE), ideal for a tackifier resin. Both Cog and TE portions
were found to exhibit high thermal decomposition temperature ensuring high
process safety. The ash was rich in magnesium oxide and has a great potential
to be used as the cure retarder in certain rubber compounds. Absence of any
deleterious metals like copper, manganese etc. was also a great positive point
towards its application standpoint.
Keywords: Natural latex, Resin, Terpenoids, Natural rubber, Thermal stability
*Corresponding Author: Tel: +91-033-235013976996/6387/8386,
Extn: 288. Email: abpoly@caluniv.ac.in
©
Smithers Rapra Technology, 2013