Poly-(3-ethyl-3-hydroxymethyl)oxetanes—Synthesis and Adhesive Interactions with Polar Substrates

Abstract

Hyperbranched polyoxetanes are a relatively new class of polymers. These are branched polyethers that are synthesized from oxetanes—four-member cyclic ethers bearing hydroxymethyl groups—via ring-opening polymerization. Four series of polyoxetanes were synthesized from 3-ethyl-3-(hydroxymethyl)oxetane and 1,1,1-tris(hydroxymethyl)propane as a core molecule. Reagents ratios ranged from 1:5 to 1:50, theoretical molar mass ranged from 714 g/mol to 5942 g/mol, and dispersities ranged from 1.77 to 3.75. The morphology of the macromolecules was investigated by a matrix-assisted laser desorption/ionization time of flight technique. The polyoxetanes’ adhesive interactions with polar materials were analyzed and provided results as follows: the work of adhesion was 101–105 mJ/m2, the bond-line tensile shear strengths were 0.39–1.32 MPa, and there was a brittle fracture mode within the polymer. The findings confirmed a good adhesion to polar substrates, but further research on polyoxetane modifications toward a reduction of brittleness is necessary.

Concurrent Enhancement of Conductivity and Stability in Water of Poly(3,4‐Ethylenedioxythiophene):Poly(Styrenesulfonate) Films Using an Oxetane Additive

“…[ 23 ] Oxetane reagents, like HMO, polymerize in acid medium, via a cationic ring‐opening mechanism (CROM), yielding linear or branched polyethers with pendant hydroxyl groups. [ 38 ] Figure depicts the suggested synthetic pathway and the general chemical structure of the graft copolymers composed of PSS covalently linked to polyether chains, these last being resultant from the CROM polymerization of HMO. In an alternative pathway, HMO monomer can first react, via the hydroxyl group, with SO 3 groups from PSS and then undergo a polymerization reaction involving free monomers.…”

“…The broad signal peaking at 3.79 ppm is attributed to the cross‐linking nodes CH 2 OS while the peaks assigned to polymerized HMO, P(HMO), are identified at 3.35, 3.22, and 0.73–0.52 ppm, these agreeing with the reported spectrum for the branched polymer from the HMO analogous, 3‐hydroxymethyl‐3‐ethyl‐oxetane. [ 38 ] In addition, the broad signal at around 7.42 ppm, assigned to 1 H in carbon atoms nearer to SO 3 groups, gets narrower, which is likely due to the lower conformational disorder of the benzene rings when bonded to the P(HMO) in the graft copolymer.…”

“…The as‐produced films are dried under regular conditions, that is, at 120 °C for 10 min, under ambient atmosphere, without any additional temperature annealing steps. Noteworthy, HMO belongs to a class of inexpensive, commercially available, water‐soluble, and low toxic oxetane‐containing building blocks, with wide applications as intermediates in organic synthesis of several classes of compounds, namely polyoxetanes, [ 38 ] cross‐linkable π‐conjugated polymers and oligomers, [ 39 ] biologically important heterocycles, [ 40 ] and most recently, in medicinal chemistry to improve “drug‐like” properties. [ 41 ] The improved water‐resistance of the produced films is demonstrated by their well‐preserved thickness, measured by atomic force microscopy (AFM) using the tip‐scratch method, and comparison of UV–visible spectra recorded before and after immersion of the films in deionized (DI) water and upon drying.…”

Synthesis of Polyhydroxyurethanes—Experimental Verification of the Box–Behnken Optimization Model

“…Respective failure modes appeared in all the series, regardless of the PHU synthesis conditions ( Figure 6 ). Thus, the determined strengths are averaged, but the values are still in the range typical for thermoplastic adhesives: poly(vinyl acetate) 0.5–3.7 MPa [ 32 ], poly(oxetane)s 0.4–1.3 MPa [ 33 ] or poly(lactide)-poly(caprolactone)-based and EVA (0.6–1.5 MPa) [ 34 ] or HDPE 1.6–2.9 MPa [ 35 ]. The computed variation coefficients for the respective series remain at the levels comparable to those found in the literature for hot-melt adhesives (i.e., 20–30%) [ 36 ].…”

Graphene Oxide Nanosheets as 2D Cationic Photoinitiators with Enhanced Photoluminescence for Chemical Patterning

“…GO-P­(δ-valerolactone) required a few hours of exposure time for clear patterning (Figure C). To increase the grafted amount, a hyperbranched polymer, GO-P­(3-ethyl-3-oxetanemethanol), was investigated. As the exposure time extended, the pattern grew thicker and became overgrown (Figure D).…”