Organic catalyst for ring opening polymerization of ε‐caprolactone in bulk. Route to starch‐<i>graft</i>‐polycaprolactone

Najemi, Loubna; Jeanmaire, Thomas; Zerroukhi, Amar; Raihane, Mustapha

doi:10.1002/star.200900198

Cited by 28 publications

(26 citation statements)

References 49 publications

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“…This suggests that the PCL chains grafted to the starch are small. It is seen that the intensity in the interactions of the hydroxyl groups of starch‐PCL increases from S1 to S5, as reported previously by Najemi et al .…”

Section: Resultssupporting

confidence: 85%

“…This is likely due to the electronegativity of the COO group of the lactone, in which the hydrogen is more acidic, in this case causing interaction with EG hydroxyls. A higher conversion rate was obtained using a mass ratio EG/MoO 3 = 1 than that reported with other types of catalysts .…”

Section: Resultscontrasting

confidence: 50%

“…The average degree of polymerization (DPn) was obtained from Eq. , as proposed by Najemi et al :

D P n (N M R) = \frac{I (H - 8) + I (H - 14)}{[I (H - 8) + I (H - 14)] - I (H - 12)}

where I ( H − X ) are integration values of the protons derived from the 1 H NMR spectrum of the starch‐g‐PCL copolymer.…”

Section: Methodsmentioning

confidence: 99%

“…For starch‐g‐PCL copolymer synthesis, a wide variety of catalysts have been used, including N‐methylimidazole (NMI), aluminum triisopropoxide [Al(OiPr) 3 ], and tin(II) 2‐ethylhexanoate [Sn(Oct) 2 ]. There are many acceptable starch sources, such as corn and potatoes, and the conversion yields obtained can reach 52% . This conversion yield is considered low because there is a 48% formation of PCL homopolymer.…”

Section: Introductionmentioning

confidence: 99%

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The effect of ethylene glycol on starch‐g‐PCL graft copolymer synthesis

et al. 2016

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The synthesis of the graft copolymer starch‐g‐PCL was carried out in a single phase, using molybdenum oxide as a catalyst, at a temperature of 150°C over a period of 24 h. Infrared spectroscopy and nuclear magnetic resonance analyses indicated that the graft copolymer was successfully synthesized, obtaining an 84% conversion yield. The introduction of ethylene glycol to the reaction influences the copolymer synthesis, affecting conversion yields and the physicochemical properties of the resultant copolymer. X‐ray diffraction analysis indicates that the copolymer crystallinity decreases as ethylene glycol concentration increases. An investigation of the thermal properties of the graft copolymer suggested that the decomposition temperature of the copolymer, compared to that of the homopolymer, decreases with exposure to ethylene glycol. Scanning electron microscopy revealed the formation of clusters between the starch granules and the grafted copolymer due to the interaction of the hydroxyl groups of the starch and PCL.

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Section: Resultssupporting

confidence: 85%

Section: Resultscontrasting

confidence: 50%

“…The average degree of polymerization (DPn) was obtained from Eq. , as proposed by Najemi et al :

D P n (N M R) = \frac{I (H - 8) + I (H - 14)}{[I (H - 8) + I (H - 14)] - I (H - 12)}

where I ( H − X ) are integration values of the protons derived from the 1 H NMR spectrum of the starch‐g‐PCL copolymer.…”

Section: Methodsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

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The effect of ethylene glycol on starch‐g‐PCL graft copolymer synthesis

et al. 2016

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“…The average degree of polymerization (DP n ) was obtained from Eq. , as given by Najemi et al :

{D P}_{normaln} true(normalN normalM normalR true) = \frac{I (H - 8) + I (H - 14)}{[I (H - 8) + I (H - 14)] - I (H - 12)}

where I ( H − X ) are the values of the integrals of the proton spectrum obtained from the 1 H NMR spectrum of the starch‐g‐PCL copolymer.…”

Section: Methodsmentioning

confidence: 99%

Chemical modification of banana starch by the in situ polymerization of ϵ-caprolactone in one step

et al. 2016

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The chemical modification of starch from physiologically immature bananas (Musa paradisiaca L.) was performed via the in situ polymerization of ϵ‐caprolactone (CL) utilizing ammonium decamolybdate as a catalyst to obtain a starch‐g‐PCL copolymer in one step. The copolymerization conditions were studied by varying the CL/catalyst mass ratio, the reaction temperature, and the reaction time. The final product was characterized using different technical instruments to demonstrate copolymerization. Based on the results, the graft copolymer was successfully synthesized, and the mass yield reached 85.2% at a temperature of 110°C with a DPn(NMR) of 10 and a Mn(NMR) of 1141 Da. The monomer conversion to copolymer followed a power‐law model with a reaction order of 3/2. The thermal properties and crystallinity of the starch and polycaprolactone in the copolymer were affected due to the formation of starch‐g‐PCL clusters.

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