Melt molding polymer composite and method of making and using the same

• US 8,487,034 B2
• Filed: 01/16/2009
• Issued: 07/16/2013
• Est. Priority Date: 01/18/2008
• Status: Active Grant

• Current Assignee: Tundra Composites, LLC.
• Original Assignee: Tundra Composites, LLC.
• Inventors: Kroll, John S., Williams, Rodney K., Heikkila, Kurt Emil
• Primary Examiner(s): Choi, Ling
• Assistant Examiner(s): LACLAIR LYNX, DARCY DANIELLE
• Application Number:
  US12/355,203
• Publication Number:
  US 20090315214A1
• Time in Patent Office: 1,642 Days
• Field of Search: 264/299, 428/372, 428/406, 428/480, 428/423.1, 428/474.4, 524/424, 524/425, 524/430, 524/433, 524/437, 524/439, 524/440, 524/441, 524/492, 524/493, 524/494, 524/431, 524/432, 524/497
• US Class Current: 524/494
• CPC Class Codes: B32B 5/16 characterised by features of a layer formed of particles, e.g. chips, powder or granules layer formed of natural mineral particles B32B19/00; layer being formed of wood fibres, chips or particles B32B21/02
• CPC Class Codes: C08K 3/08 Metals
• CPC Class Codes: C08K 7/20 Glass
• CPC Class Codes: H01F 41/00 Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties
• CPC Class Codes: Y10T 428/2927 including structurally defined particulate matter

Abstract

The invention relates to a hot melt dispensable polymeric composite and process for making and using the composite. Particulates of adequate particle size are mixed with a polymer that exhibits low viscosities at temperatures typically provided by hot-melt glue guns to form rods that vary significantly in density from the base polymer. Novel articles can be manufactured by dispensing the composite from a glue gun into molds or by placement of the melt molding compound into preformed cavities within an end article.

Claims

1. A thermoplastic composite for forming a rod-shaped article adapted to be used in hot-melt adhesive applicators or dispensers, the composite comprising:

(a) a polymer phase comprising about 0.6 to 92 wt. % and 14 to 69 vol. % of the composite, the polymer characterized by melt flow properties such that the viscosity of the polymer at 265°

C. is about 500-2000 cP; and

(b) a particulate comprising about 3 to 99.4 wt. % and 31 to 86 vol. % of the composite, the particulate intermixed with the polymer phase, the particulate having about 0.005 to 3 wt. % of a coating of an interfacial modifier wherein the interfacial modifier at least partially coats the particulate, the particulate having a particle size where no more than 10 wt. % of the particles are under 10 microns;

wherein the particulate and polymer phase comprise greater than 95 vol. % of the composite, the composite having a density of 0.2 to 16 gm- cm³ and the composite has a viscosity of less than about 100,000 cP at about the melt temperature of the composite.

2. The composite of claim 1 wherein the polymer phase comprises nylon.

3. The composite of claim 1 wherein the polymer phase comprises polyurethane.

4. The composite of claim 1 wherein the polymer phase comprises polyester.

5. The composite of claim 1, wherein the viscosity of the composite is adapted to a hand actuated applicator and the particulate comprises a mineral, a metal, a solid glass sphere, a hollow glass sphere or a mixture thereof.

6. The composite of claim 5, wherein the metal particulate is substantially metal deactivator-free.

7. The composite of claim 1 wherein the viscosity of the polymer phase at 265°

C. is about 800-1300 cP.

8. The composite of claim 1, wherein the polymer phase has a softening temperature above room temperature and the composite has a melt viscosity of lower than about 25,000 cP.

9. The composite of claim 1, wherein the polymer phase has a softening temperature above room temperature and the composite has a melt viscosity of lower than about 10,000 cP at a temperature of 130 to 250°

C.

10. The composite of claim 1, wherein the polymer phase has a softening point of about 40 to 185°

C.

11. The composite of claim 1, wherein the composite has a density of about 0.2 to 0.7 gm-cm³.

12. The composite of claim 1, wherein the composite has a density of about 4 to 18 gm- cm³.

13. The composite of claim 1, wherein the composite has a melt viscosity of about 25,000 to 500 cP at a temperature of about 100 to 240°

C.