Character of long-chain branching in highly purified natural rubber

2010 ◽  
Vol 115 (6) ◽  
pp. 3645-3650 ◽  
Author(s):  
Sureerut Amnuaypornsri ◽  
Lucksanaporn Tarachiwin ◽  
Jitladda T. Sakdapipanich
Keyword(s):  
Natural Rubber ◽  
Chain Branching ◽  
Long Chain Branching ◽  
Long Chain

Characterization of long chain branching: Dilution rheology of industrial polyethylenes

2002 ◽  
Vol 46 (2) ◽  
pp. 401-426 ◽  
Author(s):  
B. J. Crosby ◽  
M. Mangnus ◽  
W. de Groot ◽  
R. Daniels ◽  
T. C. B. McLeish
Keyword(s):  
Chain Branching ◽  
Long Chain Branching ◽  
Long Chain

The effect of long chain branching on the processability of polypropylene in thermoforming

2004 ◽  
Vol 44 (5) ◽  
pp. 973-982 ◽  
Author(s):  
A. D. Gotsis ◽  
B. L. F. Zeevenhoven ◽  
A. H. Hogt
Keyword(s):  
Chain Branching ◽  
Long Chain Branching ◽  
Long Chain

Long-Chain Branching and Mechanism Controlling Molecular Weight in Hevea Rubber

1999 ◽  
Vol 72 (4) ◽  
pp. 712-720 ◽  
Author(s):  
Jitladda Tangpakdee Sakdapipanich ◽  
Tippawan Kowitteerawut ◽  
Krisda Suchiva ◽  
Yasuyuki Tanaka
Keyword(s):  
Molecular Weight ◽  
Natural Rubber ◽  
Molecular Weight Distribution ◽  
Weight Distribution ◽  
Branch Points ◽  
Long Chain Branching ◽  
Linear Character ◽  
Close Relationship ◽  
Deproteinized Natural Rubber ◽  
Long Chain

Abstract The linear character of transesterified deproteinized natural rubber (DPNR-TE) was confirmed by the analysis of terminal groups with NMR and viscometric analyses. The branch content of DPNR rubber from fresh latex was found to range from 0.3 to 1.3 and 0.7 to 3.2, based on tri- and tetra-functionalities, respectively. The plot between the number of branch-points and molecular weight (MW) can be divided into three fractions: (A) the rubber fractions in MW ranging from 2.4×105 to 1.9×106; (B) between 1.9×105 and 2.4×105; and (C) those of MW less than 1.9×105. The fraction (A) showed the number of branch-points per a branched molecule (m) higher than that of fractions (B) and (C). This plot is superimposable with the bimodal molecular-weight distribution (MWD) of Hevea rubber, showing a good coinciding of peak-tops at the high and low MW fractions. It seems likely that there is a close relationship between the number of branch-point and bimodal MWD of natural rubber.

Sign in / Sign up

Export Citation Format

Share Document