Morphology and nonisothermal crystallization of a polyacetal/poly(ε‐caprolactone) reactive blend prepared via a chain‐transfer reaction

Abstract

A polyacetal (POM)/poly(e-caprolactone) (PCL) reactive blend prepared via a chain-transfer reaction was investigated with respect to its morphology and nonisothermal crystallization, and the results were compared with those of a simple POM/PCL blend. The reactive blend had a microscopically phase-separated morphology in which the diameter of the PCL microphase was below 100 nm, and it clearly yielded ring-banded spherulites, whereas between the two blends, there were no significant differences in the diameters and polygonal edges of the spherulites and in the long period of the POM phases. The PCL part of the reactive blend crystallized within the confined microspace with about 10% lower crystallinity than that of the corresponding simple blend. A lower Avrami exponent and crystallization rate parameter of the PCL part were observed in the primary crystallization process of the reactive blend. In contrast, the crystallinity of the POM component and the nonisothermal crystallization kinetic parameters of the POM part showed no noticeable differences between the two blends at any given cooling rate.

Creep rupture properties of homopolymer, copolymer, and terpolymer based on poly(oxymethylene)

“…The samples for the NMR measurement were purified by dissolution‐reprecipitation method by using HFIP as a solvent and methanol as a precipitant, respectively. The DOX content in the polyacetal copolymers and the DOX and EHGE contents in the polyacetal terpolymers were determined by 1 H‐NMR spectrometry according to the same methods reported previously 11–13. The signals of the CH 2 CH 2 O group assigned to the DOX unit and the CH 2 CH 2 CH 3 group assigned to the EHGE unit were detected in the spectrum of 1 H‐NMR, and the each unit content was calculated from the area of each characteristic peak.…”

Distinct Crystallization Pathways of Polyoxymethylene in Methanol System

“…The cooling process is shown in detail in Figure 1c. The POM crystallinity (Xc) was calculated according to Equation (1).…”

“…Polyoxymethylene (POM), also known as polyacetal [1], is a linear polymer with a predominantly (CH 2 O) n backbone. As a thermoplastic engineering plastic [2], it has a regular molecular structure, high density, almost no side chains, and high crystallinity, which makes the resin products produced from POM have excellent mechanical properties and good wear resistance [3].…”

Crystallization of poly(ε-caprolactone) in its immiscible blend with polylactide: insight into the role of annealing histories

“…Up to now, this blend system has been studied extensively. The reported studies mainly focus on several important aspects around structure-property relations of this system: (1) design of phase morphology and its evolution control to obtain blend with special phase structure; [3][4][5][6][7][8] (2) improvement of immiscible phase morphology by reaction processing [9][10][11] or compatibilization technology using block copolymers; [12][13][14][15][16][17][18][19] (3) dependence of thermal and mechanical properties on the compositions and hierarchical system structure; [20][21][22][23][24][25][26][27][28] (4) ow behavior and viscoelasticity of system and their relations with thermodynamic and dynamic conditions; [29][30][31][32][33] (5) evaluation of system biodegradation [34][35][36][37][38] and fabrication of porous materials or nonwovens used for tissue substrates or drug delivery; [39][40][41][42][43] (6) property and structure design by controlling selective localization of nanoparticles. [44...…”