eCommons

 

MULTI-MATERIAL THERMOSET SYNTHESIS THROUGH PHOTOSWITCHABLE POLYMERIZATIONS

Access Restricted

Access to this document is restricted. Some items have been embargoed at the request of the author, but will be made publicly available after the "No Access Until" date.

During the embargo period, you may request access to the item by clicking the link to the restricted file(s) and completing the request form. If we have contact information for a Cornell author, we will contact the author and request permission to provide access. If we do not have contact information for a Cornell author, or the author denies or does not respond to our inquiry, we will not be able to provide access. For more information, review our policies for restricted content.

No Access Until

2025-09-05
Permanent Link(s)

Other Titles

Author(s)

Abstract

The ability to fabricate multi-material thermoset with spatially controlled physical properties has been a challenge in traditional thermoset manufacturing. To address this challenge, we developed new photopolymerization methodologies that could selectively polymerize different monomers in one pot. Early on, we took advantage of a photoswitchable RAFT mechanism that could incorporate vinyl ethers and acrylates at growing polymer chain ends by switching the wavelength of light. The crosslink density could be temporally tuned by using different amount of light irradiation following the photo-controlled polymerization mechanism. By using photomasks, spatial control over the crosslink density was achieved on both macroscale and microscale. Later, we invented a new photopolymerization system that modulates a monochromatic light dosage to switch from radical to cationic polymerizations. By buffering the strong acid generation, we could incorporate acrylate and epoxide monomers selectively and tune the thermoset mechanical properties by only changing the amount of light irradiation. This methodology was also applied to switching two cationic polymerizations in one pot. Lastly in this thesis, we will discuss a hydrogen bond donor (HBD) catalyzed photoinitiated cationic polymerization from photoacid generators (PAGs). Through the formation of hydrogen bonds between a HBD and the coordinating anions in PAGs, the cationic polymer chain end propagations were significantly accelerated.

Journal / Series

Volume & Issue

Description

166 pages

Sponsorship

Date Issued

2023-08

Publisher

Keywords

3D Printing; Crosslinked Polymeric Materials; Multi-materials; Photopolymerizations

Location

Effective Date

Expiration Date

Sector

Employer

Union

Union Local

NAICS

Number of Workers

Committee Chair

Fors, Brett

Committee Co-Chair

Committee Member

Coates, Geoffrey
Lambert, Tristan

Degree Discipline

Chemistry and Chemical Biology

Degree Name

Ph. D., Chemistry and Chemical Biology

Degree Level

Doctor of Philosophy

Related Version

Related DOI

Related To

Related Part

Based on Related Item

Has Other Format(s)

Part of Related Item

Related To

Related Publication(s)

Link(s) to Related Publication(s)

References

Link(s) to Reference(s)

Previously Published As

Government Document

ISBN

ISMN

ISSN

Other Identifiers

Rights

Rights URI

Types

dissertation or thesis

Accessibility Feature

Accessibility Hazard

Accessibility Summary

Link(s) to Catalog Record