| Abstract
| - The adhesion between glass and polyethylene (high-density polyethylene (HDPE) or low-density polyethylene (LDPE)) was improved by means of polyethylene chains grafted on the glass surface.Chlorosilane-terminated polyethylene (PE) with different molar masses were synthesized in order to obtain(i) semicrystalline polymers able or not to crystallize with the free chains of the polyethylenes matricesand ( ii) polymer chains which could react with the silanol groups from the glass surface. The graftingof alkylchlorosilanes (alkyl chain length varying from C4H9 to C30H61) was considered in comparison tothe polymer chains. The adhesion developed at the polyethylene/glass interface was studied as a functionof the molar mass of functionalized-polyethylene grafted on the glass surface. For that purpose, theasymmetric double cantilever beam test was used to determine the fracture energy, Gi, of the interface.On both high-density and low-density polyethylene/glass joints, the fracture energy of the interface, Gi,was found to increase with the length of the interfacial connecting chains. The locus of the failure wasstudied by means of wettability measurements and atomic force microscopy analysis of the surfaces afterseparation. The higher values of the fracture energy of the interface with HDPE can be explained by abetter compatibility of the tethered-PE chains with the free chains of the PE matrix which are morelinear than LDPE. It was demonstrated that for the shortest chains (alkylchlorosilanes), the connectorswere extracted from the bulk PE (LDPE or HDPE) whereas for the polymeric chains, a cohesive failureoccurred for the glass/HDPE interfaces. Such a study can be used to design the connecting polymericchains for improving the adhesion between glass and a semicrystalline polymer.
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