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Barrier and mechanical properties of pulp fiber/polymer laminates and blends
Author(s) -
Krook M.,
Hedenqvist M. S.,
Albertsson A.C.,
Hellman A.,
Iversen T.,
Gedde U. W.
Publication year - 2000
Publication title -
polymer engineering and science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.503
H-Index - 111
eISSN - 1548-2634
pISSN - 0032-3888
DOI - 10.1002/pen.11148
Subject(s) - materials science , composite material , polymer , compression molding , paperboard , molar mass , copolyester , polyethylene , heat deflection temperature , pulp (tooth) , polyester , izod impact strength test , ultimate tensile strength , medicine , mold , pathology
Paperboard laminates coated with two grades of poly(ε‐caprolactone) (PCL), poly(hydroxy butyrate‐co‐valerate) (PHBV) or a liquid crystalline copolyester (LCP) were prepared by compression molding, and the influence of the processing conditions and polymer content of the laminate on the laminate properties was studied. Ligno‐cellulose fiber/polymer blends were prepared from wet pulps and PCL and PHBV. The morphology, water vapor transmission rates, creasability, curl and twist and mechanical properties of the laminates and blends were studied. LCP and slowly cooled high molar mass PCL laminated paperboards showed the best creasing properties and the paperboards that were penetrated by the polymer showed the smallest degree of curl and twist. Extensive penetration occurred during compression molding of the paperboard with the low molar mass PCL at all temperatures and with PHBV and LCP at the higher molding temperatures. The water vapor transmission rates ranged from 1 to 300 times that of polyethylene depending on the polymer used and on the thermal history. In the case of blends, competitive properties were obtained only in those with a high polymer content. The laminate stiffness decreased and the strength increased in two polymer concentration regions, at ∼20 wt% due to fiber‐fiber separation and at ∼60 wt% due to phase inversion.