PRI ageing and some related properties of constant viscosity natural rubbers (Record no. 65683)

MARC details
000 -LEADER
fixed length control field 01888nam a2200217Ia 4500
100 ## - MAIN ENTRY--AUTHOR NAME
Personal name Eng A H
245 #0 - TITLE STATEMENT
Title PRI ageing and some related properties of constant viscosity natural rubbers
260 ## - PUBLICATION, DISTRIBUTION, ETC. (IMPRINT)
Name of publisher Journal of Rubber Research
Year of publication 2002
300 ## - PHYSICAL DESCRIPTION
Number of Pages 199-208
520 ## - SUMMARY, ETC.
Summary, etc Constant viscosity natural rubber (NR) samples from different clones showed no correlation between copper content and Plasticity Retention Index (PRI) value. When the NR samples were stabilised with hydroxylamine, the degree of storage hardening was low but the PRI remained high. The gel content of the NR samples decreased significantly after the PRI test. The extent of reduction in gel content was much greater than that of the reduction in molecular weight of the NR samples. This was attributed to the denaturation of the proteins, which led to the disintegration of crosslinks, or higher rate of oxidation due to the presence of a high level of metal ions in the gel. The extent of molecular weight reduction was slightly lower than that of plasticity value. The Wallace plasticity could be correlated with the geometrical mean of Mn and Mw, i.e, (MnMw)1/2. The correlations obtained from linear regression before and after PRI ageing were quite comparable probably because the NR samples were processed and aged under the same conditions. Activation energy of oxidation (AEO) determined by differential scanning calorimeter provided a more sensitive method of assessing the ageing resistance of NR samples than PRI. However, the correlation between PRI and AEO was insignificant.
650 ## - SUBJECT ADDED ENTRY--TOPICAL TERM
Topical Term Constant viscosity
650 ## - SUBJECT ADDED ENTRY--TOPICAL TERM
Topical Term Copper content
650 ## - SUBJECT ADDED ENTRY--TOPICAL TERM
Topical Term Differential scanning calorimeter
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Topical Term Hydroxylamine
650 ## - SUBJECT ADDED ENTRY--TOPICAL TERM
Topical Term Molecular weight
650 ## - SUBJECT ADDED ENTRY--TOPICAL TERM
Topical Term Wallace plasticity
700 ## - ADDED ENTRY--PERSONAL NAME
Personal name Chang C F
700 ## - ADDED ENTRY--PERSONAL NAME
Personal name Kawahara S
942 ## - ADDED ENTRY ELEMENTS (KOHA)
Koha item type Journals
Holdings
Withdrawn status Lost status Damaged status Not for loan Home library Current library Shelving location Date acquired Serial Enumeration / chronology Koha item type
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