Trends in Synthetic Strategies for Making (CO)Polymers

Parthiban, Anbanandam

doi:10.1002/9781118860168.ch1

Cited by 2 publications

(15 citation statements)

References 54 publications

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“…The polyether used was poly(oxyhexane), also denoted poly(1,6 hexanediol) [poly (1,6 HD)], and was synthesized employing the procedure reported by Basterretxea et al 18 The self-condensation of the diol (1,6 hexanediol) was carried out, the polyether was synthesized by a multistep polymerization process, using methanesulfonic acid/ triazabicyclo[4.4.0]dec-5-ene as a noneutectic base organocatalyst.…”

Section: ■ Experimental Sectionmentioning

confidence: 99%

“…Synthesis of PET-mb-poly (1,6 HD) Copolymers. The synthesis of each copolymer was performed in a tubular Schlenk flask with a magnetic stirrer.…”

Section: ■ Experimental Sectionmentioning

confidence: 99%

“…DMT (1 equiv, 0.015 mol, 3.0 g) and EG (1.4 equiv, 0.021 mol, 1.3 g) were blended in the presence of the DBU/BA (5 mol % with respect to DMT) catalyst at 250 °C for 1.5 h at atmospheric pressure. Afterward, the previously synthesized telechelic poly(1,6 HD) was added to obtain copolymers of PET-mb-poly(1,6 HD) with different compositions of PET/poly (1,6 HD). To do the above, the quantities of DMT and EG were kept constant while the content of poly(1,6 HD) was varied as follows [PET/poly(1,6 HD), g of poly(1,6 HD)]: (68/32, 0.48 g), (64/36, 1.08 g), (61/39, 1.86), and (34/66, 4.34 g).…”

Section: ■ Experimental Sectionmentioning

confidence: 99%

“…A mixed solvent was used consisting in deuterated chloroform (CDCl 3 ) and TFA (8:1, v/v) to dissolve PET and PET-mb-poly(1,6 HD) copolymers. For poly (1,6 HD), deuterated chloroform (CDCl 3 ) was used. CDCl 3 was employed as a reference for all spectra.…”

Section: ■ Experimental Sectionmentioning

confidence: 99%

“…Combining two or more homopolymers to obtain new materials (copolymers) with properties different from those of the parent homopolymers is a frequently used strategy. 1 Poly(ethylene terephthalate) (PET) is a frequently used polymer for the manufacture of beverage bottles, amongst other multiple products. Therefore, it has been the subject of intensive research.…”

Section: ■ Introductionmentioning

confidence: 99%

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Organocatalyzed Polymerization of PET-mb-poly(oxyhexane) Copolymers and Their Self-Assembly into Double Crystalline Superstructures

et al. 2019

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Double crystalline multiblock copolymers exhibit two well-defined melting temperatures associated with the two phases formed by their constituent blocks. The crystalline superstructure formed in these copolymers is complex and depends on the miscibility of both comonomers. In this work, an innovative series of double crystalline poly(ethylene terephthalate)-mb-poly(oxyhexane) multiblock copolymers were prepared in one pot. Previously synthesized low molecular weight poly(oxyhexane)telechelic diol and poly(ethylene terephthalate) (PET) oligomers were reacted by transesterification using an organic catalyst (1,8-diazabicyclo[5.4.0]undec-7-ene/benzoic acid), in a solvent-free process. The copolymerization was demonstrated by 1H NMR and 13C NMR spectroscopies, and the random distribution of poly(oxyhexane) chains was confirmed. We found that all compositions exhibited double crystallinity, but the crystallization of the copolymers was strongly affected by the PET/poly(oxyhexane) composition. When the PET content in the copolymer decreases, the crystallization and melting temperatures of the poly(oxyhexane) phase decrease as well as its crystallization rate. The poly(oxyhexane) content increases induce similar changes in the PET phase. PET and poly(oxyhexane) chain segments form a one-phase melt according to small-angle X-ray scattering (SAXS). When the material is cooled from the melt, the PET phase crystallizes first (at higher temperatures), forming superstructural (micrometer size spherulites) templates. Upon further cooling, the crystallization of poly(oxyhexane) lamellae occurs, within the interlamellar regions of PET spherulitic templates. Furthermore, during crystallization of the copolymer, the amorphous regions of both components undergo phase separation, as evidenced by the presence of two T g’s. Polarized light optical microscopy/atomic force microscopy studies were performed and demonstrated the presence of microspherulitic morphology in the whole composition range. Considering all results, including temperature-dependent synchrotron SAXS/wide-angle X-ray scattering, we demonstrate the ability of poly(oxyhexane) to crystallize upon cooling within the previously formed PET spherulitic templates. Hence, these copolymers form complex double crystalline spherulitic superstructures which contain two amorphous and two crystalline interlamellar phases.

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Section: ■ Experimental Sectionmentioning

confidence: 99%

“…Synthesis of PET-mb-poly (1,6 HD) Copolymers. The synthesis of each copolymer was performed in a tubular Schlenk flask with a magnetic stirrer.…”

Section: ■ Experimental Sectionmentioning

confidence: 99%

Section: ■ Experimental Sectionmentioning

confidence: 99%

Section: ■ Experimental Sectionmentioning

confidence: 99%

Section: ■ Introductionmentioning

confidence: 99%