Adjustable CTE polymer compositions for extrusion and additive manufacturing processes
A polymer composition capable of being additively manufactured includes a polymer matrix and an NTE additive. The NTE additive enables tailoring of the CTE of the polymer composition and the additively manufactured structure made using the composition.
1. A method of making a composite part, the method comprising:
additively manufacturing or extruding a polymer composition to form a tool, the polymer composition comprising a polymer matrix and a negative thermal expansion (NTE) additive, and a volume of the NTE additive in the polymer composition being configured to yield the tool having a first coefficient of thermal expansion (CTE);
applying a composite part composition or composite part laminate on or to the tool, the composite part composition or composite part laminate being configured to yield the composite part having a second CTE that is generally matched to the first CTE of the tool; and
exposing the tool to sufficient heat to cure the composite part composition or composite part laminate to yield the composite part having the second CTE that is generally matched to the first CTE of the tool.
2. The method of claim 1 , wherein the NTE additive comprises a powder or particulate having an average particle size of about 10 μm or smaller.
3. The method of claim 1 , wherein the NTE additive comprises a material selected from the group consisting of: transition metal tungstates; transition metal molybdates; zirconium vanadates; zeolites exhibiting NTE; aluminum phosphates exhibiting NTE; Prussian blue analogs; antiperovskite manganese nitrides; β-eucryptite; BiNi 1−x Fe x O 3 compounds in which x is less than 1 and greater than 0; Ca 2 RuO 4−γ ; combinations thereof, hybrids thereof, and mixtures thereof.
4. The method of claim 1 , wherein the polymer composition further comprises one or more auxiliary additives.
5. The method of claim 4 , wherein the one or more auxiliary additives comprises one or more strengtheners, one or more magnetically receptive materials, or one or more colorants.
6. The method of claim 5 , wherein the one or more strengtheners comprises a material selected from the group consisting of carbon fibers, glass fibers, aramid fibers, metal fibers, metal coated fibers, and combinations thereof.
7. The method of claim 1 , wherein the NTE additive is present in the polymer composition in an amount of about 1 to about 60 vol % based on 100 vol % of the polymer composition.
8. The method of claim 1 , wherein the additively manufacturing or extruding the polymer composition comprises extruding the polymer composition to form the tool, and the tool has a constant cross-section.
9. The method of claim 1 , wherein the additively manufacturing or extruding the polymer composition comprises additively manufacturing the polymer composition to form the tool, and the tool comprises a net shape.
10. The method according to claim 4 , wherein the NTE additive and the auxiliary additives are present in the polymer composition in a sum total amount of about 1 to about 60 vol % based on 100 vol % of the polymer composition.
11. The method according to claim 1 , wherein the NTE additive comprises an NTE material coated with a coating material.
12. A method of making a composite part, the method comprising:
additively manufacturing or extruding a polymer composition to form a tool, the polymer composition comprising a polymer matrix, one or more strengtheners, and a negative thermal expansion (NTE) additive, and a volume of the NTE additive in the polymer composition being configured to yield the tool having a first coefficient of thermal expansion (CTE);
applying a composite part composition or composite part laminate on or to the tool, the composite part composition or composite part laminate configured to yield the composite part having a second CTE that is generally matched to the first CTE of the tool; and
exposing the tool to sufficient heat to cure the composite part composition or composite part laminate to yield the composite part having the second CTE that is generally matched to the first CTE of the tool.
13. The method of claim 12 , wherein the NTE additive comprises a powder or particulate having an average particle size of about 10 μm or smaller.
14. The method of claim 12 , wherein the NTE additive comprises a material selected from the group consisting of: transition metal tungstates; transition metal molybdates; zirconium vanadates; zeolites exhibiting NTE; aluminum phosphates exhibiting NTE; Prussian blue analogs; antiperovskite manganese nitrides; β-eucryptite; BiNi 1−x Fe x O 3 compounds in which x is less than 1 and greater than 0; Ca 2 RuO 4−γ ; combinations thereof, hybrids thereof, and mixtures thereof.
15. The method of claim 12 , wherein the one or more strengtheners comprises a material selected from the group consisting of carbon fibers, glass fibers, aramid fibers, metal fibers, metal coated fibers, and combinations thereof.
16. The method of claim 12 , wherein the NTE additive is present in the polymer composition in an amount of about 1 to about 60 vol % based on 100 vol % of the polymer composition.
17. The method of claim 12 , wherein the additively manufacturing or extruding the polymer composition comprises extruding the polymer composition to form the tool, and the tool has a constant cross-section.
18. The method of claim 12 , wherein the additively manufacturing or extruding the polymer composition comprises additively manufacturing the polymer composition to form the tool, and the tool comprises a net shape.
19. The method of claim 12 , wherein the NTE additive and the one or more strengtheners are present in the polymer composition in a sum total amount of about 1 to about 60 vol % based on 100 vol % of the polymer composition.
20. The method of claim 12 , wherein the NTE additive comprises an NTE material coated with a coating material.