Novel triple-shape PCU/PPDO interpenetrating polymer networks constructed by self-complementary quadruple hydrogen bonding and covalent bonding

Triple-shape memory effects of modified semicrystalline ethylene–propylene–diene rubber/poly(ε-caprolactone) blends

“…8 presents the cyclic triple-shape program for the A-EPDM/PCL (70/30) blend. To avoid residual stresses from the processing history of the samples, F and R were determined based on 2-3 cycles, as reported in Table 4 [19]. In cycle 2, when a stress of 0.02 MPa was applied at 130°C, the strain was increased to 23.1% from 12.5%, as shown in Fig.…”

“…Triple-shape memory properties of the blends were measured using DMA Q800 under a controlled-force mode according to previous articles [14,19,30]. A four-step program was employed on the DMA.…”

“…The incorporation of INCh promotes the bonded PU segment to change into a glassy form by restraining the movement of polymer chains, which is responsible for the triple-shape memory property of the SMPU/INCh composites. Yang and coworkers [19] synthesized a T-SMP based on interpenetrating polymer networks (IPNs) with two different crystalline melting transitions; this T-SMP consisted of 2-ureido-4-pyrimidinone-functio nalized poly(caprolactone)/poly(p-dioxane), which can form a crosslinked structure via self-complementary quadruple hydrogen bonding and covalent bonding, respectively. Hu and coworkers [21] observed T-SME in segmented polyurethanes with two different crystalline switching phases (PCL and PTMG) in proper compositions.…”

“…Triple-shape memory effect (T-SME) can be manifested in a crosslinked multiphase polymer system having two distinct and well-defined crystalline melting and/or glass transition temperatures [17][18][19][20][21][22][23][24]. Zhou and coworkers [10] developed a molecular composite that exhibit T-SME by incorporating a mesogenic unit, cholesteryl isonicotinate (INCh), into the shape memory polyurethane (SMPU) containing carboxylic groups.…”

Shape-memory poly(p-dioxanone)–poly(ɛ-caprolactone)/sepiolite nanocomposites with enhanced recovery stress

“…The blooming development of the polymer nanocomposites provides an efficient strategy to realize significant improvement of the performance upon a small amount of filler in nanoscale, such as carbon nanotubes (CNTs) and nanoclay [7]. Recently, the crystalline aliphatic polyesters such as poly(p-dioxanone) (PPDO) [8] and poly(e-caprolactone) (PCL) have been utilized to develop the SMPs [9][10][11]. The previous work of Lendlein [11] demonstrated that PPDO-PCL copolymers display very good shape memory performance with a suitable hard domain (PPDO) and switching domain (PCL) content.…”