Self‐Immolative Poly(4,5‐dichlorophthalaldehyde) and its Applications in Multi‐Stimuli‐Responsive Macroscopic Plastics

Abstract

End-capped poly(4,5-dichlorophthalaldehyde) (PCl2PA), which is a new self-immolative CD(r) polymer with the unique capability of depolymerizing continuously and completely in the solid state when an end cap is cleaved from the polymer by reaction with a specific molecular signal, is described. End-capped poly(4,5-dichlorophthalaldehyde) is sufficiently stable to enable patterning of three-dimensional macroscopic polymeric materials by selective laser sintering. These unique materials are capable of 1) autonomously amplifying macroscopic changes in the material in response to specific molecular inputs, and 2) altering their responses depending on the identity of the applied signal. Thus, not only does end-capped PCl2PA provide new and unique capabilities compared to the small subset of existing CD(r) polymers, but it also provides access to a new class of stimuli-responsive materials.

Decomposable and Template Polymers: Fundamentals and Applications

“…In recent years, phthalaldehyde has garnered increased interest due to the ease of synthesis and new controllability of the end-groups [101]. Several studies have looked at the kinetics and reaction conditions to achieve reproducible and high-quality polyphthalaldehyde [101][102][103][104]. Figure 16 shows a typical phthalaldehyde synthesis.…”

“…The added stability allowed targeted degradation of different layers of similar polymer based on the endcap triggers. Layers of poly(4,5-dichlorophthalaldehyde) in a multilayer structure were selectively depolymerized by exposure to different triggering agents [104].…”

Determination of ceiling temperature and thermodynamic properties of low ceiling temperature polyaldehydes

“…INTRODUCTION Self-immolative polymers are of interest due to their ability to rapidly depolymerize when triggered. [1][2][3][4][5][6][7] Self-immolative polymers which depolymerize into small monomer units can be used in applications such as drug delivery, dry developing photoresists, transient electronics, and recyclable plastics. 8,9 The intrinsic value of selfimmolative polymers comes from their thermodynamic properties.…”

Rapid, On‐Command Debonding of Stimuli‐Responsive Cross‐Linked Adhesives by Continuous, Sequential Quinone Methide Elimination Reactions

“…Our design is based on using cross-linking to form an adhesive (polymer 1 in Figure 1) and de-cross-linking to debond the adhesive (polymer 2). In this design, less than 1mol %o fas timuli-responsive monomer (in the form of am acromonomer) is needed to cross-link an abundant, readily accessible monomer to create as trong, stimuliresponsive adhesive.S timuli-induced depolymerization [3,4] of the macro-cross-linker (a poly(benzyl ether)) leads to disproportionately large changes in the structure,w hich enable the selective,s ensitive,a nd rapid switching of as trong adhesive into ad ebonded material. Depolymerization provides these features because it breaks many cross-links simultaneously and thus gives rise to amplified changes in the structure and properties of the adhesive.…”