Thermodynamics of fusion of poly-β-propiolactone and poly-ϵ-caprolactone. comparative analysis of the melting of aliphatic polylactone and polyester chains

Crescenzi, V.; Manzini, Giorgio; Calzolari, G.; Borri, Claudio

doi:10.1016/0014-3057(72)90109-7

Cited by 705 publications

(484 citation statements)

References 13 publications

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“…The main peaks in the FTIR and NIR spectra for the PCL/FU tablets were the same as those observed in the spectra for the pure PCL tablets. The existence of peaks at 600 cm - *Crystallinity values based in the enthalpy of melting of 100% crystalline PCL, 142.0 J/g [30]. For the PCL/FU tablets, only 90 % of the weight was considered in the PCL crystallinity calculus, since 10 % was FU.…”

Section: Discussionmentioning

confidence: 99%

3D printing of PCL/Fluorouracil tablets by selective laser sintering: Properties of implantable drug delivery for cartilage cancer treatment

Gv¹,

Fe²,

Gb³

et al. 2017

Rheumatol Orthop Med

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In this study, implantable polycaprolactone/fluorouracil tablets were additively manufactured by selective laser sintering using different laser power levels. PCL/FU tablets showed on SEM-EDS small particles of fluorouracil dispersed on the surface and into the porous PCL matrix. The crystallinity values for the PCL/FU tablets were lower than for the pure PCL tablets, probably due to interaction of the FU particles with the polymer chains during the solidification process. The PCL/FU tablets prepared using the higher laser power (7 W) had the highest flexural modulus, probably due to better PCL particle coalescence, higher sinter degree and the dispersion of FU particles in the co-continuous porous PCL matrix. Initially the PCL/FU tablets provided a rapid release of a high concentration of the drug at the site of the cancer cells and a subsequent controlled release sustaining levels of the chemotherapeutic agent in the region of the tumor. This 2-stage release of the drug can be a desirable profile in cartilage cancer treatment.

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Section: Discussionmentioning

confidence: 99%

3D printing of PCL/Fluorouracil tablets by selective laser sintering: Properties of implantable drug delivery for cartilage cancer treatment

Gv¹,

Fe²,

Gb³

et al. 2017

Rheumatol Orthop Med

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“…Toughness of the P(3HB-co-3HH)/PCL blend K Katsumata et al DH 0 the melting enthalpy of a perfectly crystallized material (¼142 J g À1 for PCL 30 and ¼146 J g À1 for P(3HB) 31 ). The DH 0 of P(3HB) was also used to measure the crystallinity of P(3HB-co-3HH)s because only the P(3HB)-type crystal forms in P(3HB-co-3HH)s. 7 In each blend, the crystallinity of P(3HB-co-3HH) was almost the same for any composition, whereas that of PCL decreased as its concentration was reduced.…”

Section: Crystals Of Blend Componentsmentioning

confidence: 99%

The toughening effect of a small amount of poly(ɛ-caprolactone) on the mechanical properties of the poly(3-hydroxybutyrate-co-3-hydroxyhexanoate)/PCL blend

Katsumata

Saitō

Fang

et al. 2011

Polym J

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To improve the mechanical properties of bacterial poly(3-hydroxybutyrate) [P(3HB)] and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) [P(3HB-co-3HH)], the materials were blended with poly(e-caprolactone) (PCL). The P(3HB-co-7 mol% 3HH) cast film and the P(3HB-co-11 mol% 3HH) melt-pressed film show brittleness after aging, although unaged samples show ductile behavior. However, the addition of a small amount of PCL was found to greatly improve the toughness of the P(3HB-co-7 mol% 3HH) cast film and the P(3HB-co-11 mol% 3HH) melt-pressed film. Reduction in the whitening of the elongated P(3HB-co-7 mol% 3HH) film by blending with PCL indicates that a transition in the deformation mechanism of the film was induced. In P(3HB-co-11 mol% 3HH)/PCL melt-pressed films, a cloud of craze initiation created by the dispersed PCL was observed. Differential scanning calorimetry thermograms and scanning electron microscopy images of the blended films indicated that finely dispersed PCL, the crystallization of which was restricted, and/or voids formed during preparation contribute to the delocalization of the applied stress and ductile deformation of P(3HB-co-3HH) films. In conclusion, the transition in the deformation mechanisms and the delocalization of the applied stress are expected to be important for enhancing the toughness of aged P(3HB-co-3HH)s, and blending with a small amount of PCL is a simple way to improve the mechanical properties of P(3HB-co-3HH)s. Polymer Journal (2011) 43, 484-492; doi:10.1038/pj.2011.12; published online 23 February 2011Keywords: blend; mechanical property; polyhydroxyalkanoate; poly(e-caprolactone); tensile test INTRODUCTION Several kinds of polyhydroxyalkanoates (PHAs) are biosynthesized by various bacteria as energy-storage materials. 1-5 They may be produced from renewable natural resources and have biodegradability. Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) [P(3HB-co-3HH)] is part of the PHA family. 6 Doi et al. 7 have found that the content of the 3HH unit greatly affected the thermal and mechanical properties of P(3HB-co-3HH), but had little effect on the crystalline structure of 3HB-rich P(3HB-co-3HH)s because of the formation of the P(3HB)-homopolymer-type crystalline phase and the exclusion of the 3HH unit from the crystalline lattice. P(3HB-co-3HH) was found to show improved mechanical properties and thermal plasticity over those of known PHAs. 8,9 One of the notable advantages of P(3HB-co-3HH)s is their adjustable mechanical properties, from soft to hard material, depending on the comonomer-unit composition; this allows for the tailoring of P(3HB-co-3HH) to various societal applications, such as in green and sustainable polymeric materials.However, P(3HB-co-3HH) becomes brittle after aging at room temperature, thus restricting its practical applications. Although

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“…) is the enthalpy of fusion of fully crystalline PCL, taken as 135.44 J g -1 [53][54][55][56]. The T m as measured from DSC analysis is (64.6 ± 0.2) °C, whilst the X c is (51.7 ± 0.5) %.…”

Section: Differential Scanning Calorimetry (Dsc)mentioning

confidence: 99%

High-pressure rheological analysis of CO2-induced melting point depression and viscosity reduction of poly(ε-caprolactone)

Curia

Focatiis

Howdle

2015

Polymer

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(2015) High-pressure rheological analysis of CO2-induced melting point depression and viscosity reduction of poly(ε-caprolactone). Polymer, Access from the University of Nottingham repository: http://eprints.nottingham.ac.uk/45413/1/curia_polymer2015_preprint.pdf Copyright and reuse:The Nottingham ePrints service makes this work by researchers of the University of Nottingham available open access under the following conditions. This article is made available under the Creative Commons Attribution Non-commercial No Derivatives licence and may be reused according to the conditions of the licence. For more details see: http://creativecommons.org/licenses/by-nc-nd/2.5/ A note on versions:The version presented here may differ from the published version or from the version of record. If you wish to cite this item you are advised to consult the publisher's version. Please see the repository url above for details on accessing the published version and note that access may require a subscription. Furthermore, a significant decrease in the viscosity of two PCL grades with different molecular weight (M n~1 0 kDa and 80 kDa) was also detected upon increasing the CO 2 pressure to 300 bar.Experimental viscosity data were fitted to the Carreau model to quantify the extent of the plasticising effects on the zero-shear viscosity and relaxation time under different conditions. Similar analyses were conducted under high-pressure nitrogen, to compare the effects obtained in the presence of a non-plasticising gas.

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Thermodynamics of fusion of poly-β-propiolactone and poly-ϵ-caprolactone. comparative analysis of the melting of aliphatic polylactone and polyester chains

Cited by 705 publications

References 13 publications

3D printing of PCL/Fluorouracil tablets by selective laser sintering: Properties of implantable drug delivery for cartilage cancer treatment

3D printing of PCL/Fluorouracil tablets by selective laser sintering: Properties of implantable drug delivery for cartilage cancer treatment

The toughening effect of a small amount of poly(ɛ-caprolactone) on the mechanical properties of the poly(3-hydroxybutyrate-co-3-hydroxyhexanoate)/PCL blend

High-pressure rheological analysis of CO2-induced melting point depression and viscosity reduction of poly(ε-caprolactone)

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