Polymer-based resin compositions derived from cellulose and articles made using these compositions

Patent metadata

Field	Value
Publication number	US-10919984-B2
Application number	US-201716348550-A
Country	US
Kind code	B2
Filing date	Nov 9, 2017
Priority date	Nov 11, 2016
Publication date	Feb 16, 2021
Grant date	Feb 16, 2021

Abstract

An injection molded article comprising a thin-walled body portion formed from a polymer-based resin derived from cellulose, wherein the thin-walled body portion comprises:
i. a gate position; ii. a last fill position; iii. a flow length to wall thickness ratio greater than or equal to 100, wherein the flow length is measured from the gate position to the last fill position; and iv. a wall thickness less than or equal to about 2 mm; and wherein the polymer-based resin has an HDT or at least 95° C., a bio-derived content of at least 20 wt %, and a spiral flow length of at least 3.0 cm, when the polymer-based resin is molded with a spiral flow mold with the conditions of a barrel temperature of 238° C., a melt temperature of 246° C., a molding pressure of 13.8 MPa, a mold thickness of 0.8 mm, and a mold width of 12.7 mm.

First claim

That which is claimed is:

1. An injection molded article comprising a thin-walled body portion formed from a polymer-based resin derived from cellulose,
wherein the thin-walled body portion comprises:
i. a gate position;
ii. a last fill position;
iii. a flow length to wall thickness ratio greater than or equal to 100, wherein the flow length is measured from the gate position to the last fill position; and
iv. a wall thickness less than or equal to about 2 mm; and

wherein the polymer-based resin is a cellulose ester composition that comprises an impact modifier in an amount from 1 to 30 wt % and a plasticizer in an amount from 0 to 10 wt %, based on the weight of the cellulose ester composition, and
wherein the polymer-based resin has an HDT or at least 95° C., a bio-derived content of at least 20 wt %, and a spiral flow length of at least 3.0 cm, when the polymer-based resin is molded with a spiral flow mold with the conditions of a barrel temperature of 238° C., a melt temperature of 246° C., a molding pressure of 13.8 MPa, a mold thickness of 0.8 mm, and a mold width of 12.7 mm.

2. The injection molded article according to claim 1 , wherein the flow length to wall thickness ratio is in the range from 250 to 1500.

3. The injection molded article according to claim 2 , wherein the flow length to wall thickness ratio is in the range from 500 to 1500.

4. The injection molded article according to claim 1 , wherein the wall thickness is in the range from 0.1 to 1.5 mm.

5. The injection molded article according to claim 4 , wherein the wall thickness is in the range from 0.1 to 1.0 mm.

6. The injection molded article according to claim 5 , wherein the wall thickness is in the range from 0.1 to 0.5 mm.

7. The injection molded article according to claim 1 , wherein the polymer-based resin has an HDT in the range from 100° C. to 140° C.

8. The injection molded article according to claim 1 , wherein the polymer-based resin has a bio-derived content in the range from 40 wt % to 60 wt %.

9. The injection molded article according to claim 1 , wherein the polymer-based resin has a spiral flow length of at least 5.0 cm.

10. The injection molded article according to claim 1 , wherein the polymer-based resin further comprises at least one property chosen from: flexural modulus of greater than 1900 MPa as measured according to ASTM D790 using a 3.2 mm thick bar hat has been subjected to 50% relative humidity for 48 hours at 23° C.; a notched izod impact strength of greater than 80 J/m as measured according to ASTM D256 using a 3.2 mm thick bar hat has been subjected to 50% relative humidity for 48 hours at 23° C.; a flex creep deflection of less than 12 mm, measured using a molded bar having dimensions of 5″ length, 0.5″ width, and 0.125″ thickness positioned horizontally on a fixture with a 4″ span, inside a dry oven for 68 hours at 90° C. with a nominal 500 psi stress on the center of the span; a transmission of at least 70 measured according to ASTM D1003 using a 3.2 mm plaque after injection molding at a barrel set point of 249° C. and a residence time of 5 min; a ΔE value of less than 25, using a 3.2 mm plaque after injection molding with a barrel temperature of 249° C. and a residence time of 5 min; or an L* color of at least 85, measured according to ASTM E1348 using a 3.2 mm plaque after injection molding with a barrel temperature of 249° C. and a residence time of 5 min.

11. The injection molded article according to any of claim 10 , wherein the polymer-based resin comprises at least 2 of the listed properties.

12. The injection molded article according to claim 1 , wherein the polymer-based resin contains no plasticizer.

13. The injection molded article according to claim 1 , wherein the gate position comprises a gate having a gate size, wherein ratio of gate size to wall thickness 0.5:1 or less.

14. The injection molded article according to claim 13 , wherein the gate size is in the range from 0.1 to 0.5 mm.

15. The injection molded article according to claim 14 , wherein the wall thickness is in the range from 0.2 to 1.0 mm or less.

16. The injection molded article according to claim 1 , wherein the polymer-based resin comprises a cellulose ester chosen from cellulose acetate propionate (CAP), cellulose acetate (CA), or combinations thereof.

17. The injection molded article according to claim 16 , wherein the cellulose ester is CAP and the polymer-based resin comprises 0-1 wt % plasticizer.

18. The injection molded article according to claim 17 , wherein the polymer-based resin comprises CAP and contains no plasticizer.

19. The injection molded article according to claim 16 , wherein the cellulose ester is CA and the polymer-based resin comprises 1-10 wt % plasticizer.

20. The injection molded article according to claim 19 , wherein the polymer-based resin comprises CA and contains plasticizer in an amount from 1 to less than 10 wt %.

Assignees

• Eastman Chem Co

Inventors

• Feng Wenlai
• An Haining
• Donelson Michael Eugene
• Pecorini Thomas Joseph
• Mccrary Robert Ellis
• Carico Douglas Weldon
• Gilliam Spencer Allen

Classifications

• B29C2945/76668

  barrel · CPC title

• B29C2945/76561

  duration · CPC title

• B29C2945/76531

  Temperature · CPC title

• B29C2945/76498

  Pressure · CPC title

• B29C45/78

  of temperature · CPC title