| 摘要 |
A heat fusible rod which is substantially uniform in cross-section along its length, which is flexible enough to be coiled on a reel and unwound therefrom, and which is sufficiently stiff to be pushed endwise into a passageway of an apparatus adapted to melt the rod and apply it to a workpiece in which passageway the rod fits snugly, comprises an outer sheath of a first material, which is stable and comprises a heat fusible synthetic polymer, which sheath surrounds a core of a second material which is also heat fusible, the two materials being such that when the rod is melted and the two molten materials mixed together, a molten adhesive composition is provided which may be applied to a workpiece. Said first material may be, for example, polyethylene or a polyamide (such as that obtained by reacting polymerized soy bean oil fatty acid with ethylenediamine); the polyethylene may be combined with an ethylene/ethyl acrylate copolymer or a hydrocarbon resin, e.g. a beta-pinene resin. Said second material may be (a) a vinyl acetate homopolymer or copolymer, e.g. a vinyl acetate/ethylene copolymer; this may be optionally admixed with, for example, a soft tacky thermoplastic saturated hydrocarbon resin or a styrene polymer, (b) a mixture of a beta-pinene polymer, an isobutylene polymer (e.g. an isobutylene-isoprene copolymer), a polyamide and an epoxide resin, and (c) a gum rosin comprising abietic acid. The second material may also include a plasticizer, e.g. dibutyl phthalate, for the first material. |
