Stress-strain behavior of low-density polyethylene/poly(methyl methacrylate) blends with modulated interfaces with a hydrogenated polybutadiene-block-poly(methyl methacrylate) diblock copolymer
[en] The stress-strain diagrams and ultimate tensile properties of uncompatibilized and compatibilized hydrogenated polybutadiene-block-poly(methyl methacrylate) (HPB-b-PMMA) blends with 20 wt % poly(methyl methacrylate) (PMMA) droplets dispersed in a low-density polyethylene (LDPE) matrix were studied. The HPB-b-PMMA pure diblock copolymer was prepared via controlled living anionic polymerization. Four copolymers, in terms of the molecular weights of the hydrogenated polybutadiene (HPB) and PMMA sequences (22,000-12,000, 63,300-31,700, 49,500-53,500, and 27,700-67,800), were used. We demonstrated with the stress-strain diagrams, in combination with scanning electron microscopy observations of deformed specimens, that the interfacial adhesion had a predominant role in determining the mechanism and extent of blend deformation. The debonding of PMMA particles from the LDPE matrix was clearly observed in the compatibilized blends in which the copolymer was not efficiently located at the interface. The best HPB-b-PMMA copolymer, resulting in the maximum improvement of the tensile properties of the compatibilized blend, had a PMMA sequence that was approximately half that of the HPB block. Because of the much higher interactions encountered in the PMMA phase in comparison with those in HPB (LDPE), a shorter sequence of PMMA (with respect to HPB but longer than the critical molecular weight for entanglement) was sufficient to favor a quantitative location of the copolymer at the LDPE/PMMA interface.
Research Center/Unit :
Center for Education and Research on Macromolecules (CERM)
Disciplines :
Materials science & engineering Chemistry
Author, co-author :
Harrats, Charef; Katholieke Universiteit Leuven (KUL) > Department of Chemistry > Laboratory for Macromolecular Structural Chemistry
Benabdallah, T.; ENSET/ORAN, Algeria > Département Génie Mécanique
Groeninckx, Gabriel; Katholieke Universiteit Leuven (KUL) > Department of Chemistry > Laboratory for Macromolecular Structural Chemistry
Jérôme, Robert ; Université de Liège - ULiège > Department of Chemistry > Center for Education and Research on Macromolecules (CERM)
Language :
English
Title :
Stress-strain behavior of low-density polyethylene/poly(methyl methacrylate) blends with modulated interfaces with a hydrogenated polybutadiene-block-poly(methyl methacrylate) diblock copolymer
Publication date :
01 January 2005
Journal title :
Journal of Polymer Science. Part B, Polymer Physics
ISSN :
0887-6266
eISSN :
1099-0488
Publisher :
John Wiley & Sons, Hoboken, United States - New Jersey