Polymer glass transition temperature manipulation via Z/E hydrazone photoswitching

Patent metadata

Field	Value
Publication number	US-11566089-B2
Application number	US-202017017222-A
Country	US
Kind code	B2
Filing date	Sep 10, 2020
Priority date	Sep 13, 2019
Publication date	Jan 31, 2023
Grant date	Jan 31, 2023

Abstract

In an embodiment, the present disclosure pertains to a method of changing the glass transition temperature of a polymer. In some embodiments, the polymer includes at least one hydrazone-containing compound. In general, the methods of the present disclosure include one or more of the following steps of: (1) applying light to the polymer; and (2) thereby changing the glass transition temperature of the polymer. In another embodiment, the present disclosure pertains to a polymer having a light-adjustable glass transition temperature. In some embodiments, the polymer includes at least one hydrazone-containing compound.

First claim

What is claimed is:

1. A method of changing the glass transition temperature (T g ) of a polymer, wherein the polymer is covalently linked to at least one hydrazone-containing compound, and wherein the method comprises:
applying light to the polymer,
wherein the light changes the glass transition temperature (T g ) of the polymer, and wherein the polymer is selected from the group consisting of polyethylene, polypropylene, polystyrene, poly(vinyl chloride), polyisobutylene, poly(methyl acrylate), poly(methyl methacrylate), polytetrafluoroethylene, poly(acrylic acid), polyacrylamide, polyacrylonitrile, poly(hydroxyethyl methacrylate), poly(hydroxyethyl acrylate), and combinations thereof.

2. The method of claim 1 , wherein the polymer is selected from the group consisting of poly(methyl methacrylate), poly(methyl acrylate), (hydroxyethyl methacrylate), poly(hydroxyethyl acrylate), and combinations thereof.

3. The method of claim 1 , wherein the at least one hydrazone-containing compound is part of a side chain of the polymer.

4. The method of claim 1 , wherein the at least one hydrazone-containing compound comprises:

or combinations thereof, and wherein Y, R 1 and R 2 are each independently selected from the group consisting of H, alkyl groups, alkenyl groups, alkoxy groups, aryl groups, ketone groups, amine groups, amide groups, carboxyl groups, carboxylic acid groups, ester groups, thiol groups, sulfoxide groups, alcohol groups, alkyne groups, azide groups, the polymer, and combinations thereof.

5. The method of claim 4 , wherein Y, R 1 and R 2 each independently comprises the polymer.

6. The method of claim 1 , wherein the at least one hydrazone-containing compound comprises:

or combinations thereof, and
wherein Y, R 1 and R 2 are each independently selected from the group consisting of CH 2 CH 3 , C(CH 3 ), (CH 2 ) 5 CH 3 , (CH 2 ) 7 CH 3 , (CH 2 ) 9 CH 3 , (CH 2 ) 11 CH 3 , (CH 2 ) 1-20 CH 3 , t-butyl, n-hexyl, n-octyl, n-decyl, n-dodecyl,

wherein n is an integer of more than 1.

7. The method of claim 1 , wherein the at least one hydrazone-containing compound is selected from the group consisting of:

and combinations thereof, wherein n is an integer of more than 1.

8. The method of claim 1 , wherein the light is derived from a light source selected from the group consisting of an arc lamp system, short-wave ultraviolet lamps, incandescent lamps, gas-discharge lamps, ultraviolet light emitting diodes, ultraviolet lasers, tunable vacuum ultraviolet systems, natural light, and combinations thereof.

9. The method of claim 1 , wherein the change in T g occurs through photo-isomerization, and wherein the hydrazone in the at least one hydrazone-containing compound transitions from a Z state to an E state upon photoisomerization.

10. The method of claim 1 , wherein the change in T g occurs through photo-isomerization, and wherein the hydrazone in the at least one hydrazone-containing compound transitions from an E state to a Z state upon photoisomerization.

11. The method of claim 1 , wherein the application of light increases T g , and wherein the increase in T g results in stiffening of the polymer.

12. The method of claim 1 , wherein the application of light decreases T g , and wherein the decrease in T g results in softening of the polymer.

13. A polymer comprising a light-adjustable glass transition temperature (T g ), wherein the polymer is covalently linked to at least one hydrazone-containing compound, and wherein the at least one hydrazone-containing compound is selected from the group consisting of:

and combinations thereof, wherein n is an integer of more than 1.

14. The polymer of claim 13 , wherein the polymer is selected from the group consisting of acrylate polymers, methyl acrylate polymers, polyethylene, polypropylene, polystyrene, poly(vinyl chloride), polyisobutylene, poly(methyl acrylate), poly(methyl methacrylate), polytetrafluoroethylene, poly(acrylic acid), polyacrylamide, polyacrylonitrile, poly(hydroxyethyl methacrylate), poly(hydroxyethyl acrylate), and combinations thereof.

15. A polymer comprising a light-adjustable glass transition temperature (T g ), wherein the polymer is covalently linked to at least one hydrazone-containing compound, wherein the at least one hydrazone-containing compound comprises:

or combinations thereof, and wherein Y, R 1 and R 2 each independently comprises the polymer.

16. A method of changing the glass transition temperature (T g ) of a polymer, wherein the polymer is covalently linked to at least one hydrazone-containing compound, and wherein the method comprises:
applying light to the polymer, wherein the light changes the glass transition temperature (T g ) of the polymer,
wherein the at least one hydrazone-containing compound comprises:

or combinations thereof, and wherein Y, R 1 and R 2 each independently comprises the polymer.

17. A method of changing the glass transition temperature (T g ) of a polymer, wherein the polymer is covalently linked to at least one hydrazone-containing compound, and wherein the method comprises:
applying light to the polymer, wherein the light changes the glass transition temperature (T g ) of the polymer,
wherein the at least one hydrazone-containing compound comprises:

or combinations thereof, and
wherein Y, R 1 and R 2 are each independently selected from the group consisting of CH 2 CH 3 , C(CH 3 ), (CH 2 ) 5 CH 3 , (CH 2 ) 7 CH 3 , (CH 2 ) 9 CH 3 , (CH 2 ) 11 CH 3 , (CH 2 ) 1-20 CH 3 , t-butyl, n-hexyl, n-octyl, n-decyl, n-dodecyl,

wherein n is an integer of more than 1.

18. A method of changing the glass transition temperature (T g ) of a polymer, wherein the polymer is covalently linked to at least one hydrazone-containing compound, and wherein the method comprises:
applying light to the polymer, wherein the light changes the glass transition temperature (T g ) of the polymer, and
wherein the at least one hydrazone-containing compound is selected from the group consisting of:

Assignees

• Dartmouth College

Inventors

• Abrahamian Ivan
• Yang Sirun
• Jeliazkov Laura L
• Harris Jared D

Classifications

• C08F8/48

  Isomerisation; Cyclisation · CPC title

• C08F20/34

  Esters containing nitrogen {, e.g. N,N-dimethylaminoethyl (meth)acrylate} · CPC title

• C08F220/30

  containing aromatic rings in the alcohol moiety · CPC title

• C08F222/22

  Esters containing nitrogen · CPC title

• C08F20/36 Primary

  containing oxygen in addition to the carboxy oxygen {, e.g. 2-N-morpholinoethyl (meth)acrylate or 2-isocyanatoethyl (meth)acrylate} · CPC title