Linked Life Data

9644597

Source:http://linkedlifedata.com/resource/pubmed/id/9644597

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1998-9-23
pubmed:abstractText
Pseudomonas resinovorans produces a medium-chain-length poly(hydroxyalkanoate) (MCL-PHA) copolymer when grown on tallow (PHA-tal). This polymer had a repeat unit composition ranging from C4 to C14 with some mono-unsaturation in the C12 and C14 alkyl side chains. Thermal analysis indicated that the polymer was semi-crystalline with a melting temperature (T(m)) of 43.5 +/- 0.2 degrees C and a glass transition temperature (Tg) of -43.4 +/- 2.0 degrees C. The presence of unsaturated side chains allowed crosslinking by gamma-irradiation. Irradiated polymer films had decreased solubility in organic solvents that indicated an increase in the crosslinking density within the film matrix. The addition of linseed oil to the gamma-irradiated film matrix enhanced polymer recovery while minimizing chain scission. Linseed oil also caused a decrease in the enthalpy of fusion (delta Hm) of the films (by an average of 60%) as well as enhanced mineralization. The effects of crosslinking on the mechanical properties and biodegradability of the polymer were determined. Radiation had no effect on the storage modulus (E') of the polymer. However, radiation doses of 25 and 50 kGy did increase the Young modulus of the polymer by 129 and 114%, and the tensile strength of the polymer by 76 and 35%, respectively. Finally, the formation of a higher crosslink density within the polymer matrix decreased the biodegradability of the PHA films.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0141-8130
pubmed:author
pubmed:issnType
Print
pubmed:volume
23
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
61-72
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Radiation crosslinking of a bacterial medium-chain-length poly(hydroxyalkanoate) elastomer from tallow.
pubmed:affiliation
United States Department of Agriculture, Eastern Regional Research Center, Wyndmoor, PA 19038, USA. rashby@arserrc.gov
pubmed:publicationType
Journal Article