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Thursday, 15 June 2017

Erratum to: Dry jet-wet spinning of strong cellulose filaments from ionic liquid solution

Published Date
Volume 24, Issue 7pp 3109–3110

Author
  • Lauri K. J. Hauru
  • Michael Hummel
  • Anne Michud
  • Herbert Sixta
  1. 1.
Erratum
DOI: 10.1007/s10570-017-1305-y
Cite this article as:
Hauru, L.K.J., Hummel, M., Michud, A. et al. Cellulose (2017) 24: 3109. doi:10.1007/s10570-017-1305-y
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For the spinning system, the manufacturer’s software reported an incorrect extrusion flow rate ve (ml min−1). The correct values for ve may be obtained by multiplying the reported ve with 1/0.6. As DR is determined from ve, it is also affected: To obtain correct DR, multiply the reported DR with 0.6. The figures are modified as follows:
ve reported
ve
DR reported
DR
0.01
0.017
1
0.6
0.02
0.033
2
1.2
0.03
0.050
3
1.8
0.04
0.067
4
2.4
0.045
0.075
5
3.0
0.05
0.083
6
3.6
  
7
4.2
  
7.5
4.5
  
8
4.8
  
9
5.4
  
10
6.0
  
11
6.6
  
12
7.2
  
12.5
7.5
  
13
7.8
Thus, the maximum DR is 7.5 at 0.033 ml min−1 rather than 12.5 at 0.02 ml min−1. Conclusions remain otherwise intact.
In section “Linear density (titer)” in Eq. 2, referring to Fig. 2, the constant factor is 13.88 ± 0.14 dtex and the factor s = 1.236 ± 0.013, instead of 22.4 ± 0.4 dtex and 1.994 ± 0.004. Referring to Fig. 3 with both variable ve and DR, the constant factor is 13.9 ± 0.01 dtex and s = 1.238 ± 0.001 instead of 23.1 ± 0.02 dtex and 2.063 ± 0.02. This result implies less shrinking of the fiber volume than reported.
In section “Tenacity and modulus,” for the relation between tenacity and draw ratio, the equation σ = σmax(1 − a/DR) has the factor a = 0.31 ± 0.02 instead of 0.51 ± 0.04.
In section “Orientation,” the draw ratio dependency of orientation is Δn = (0.044 ± 0.001)–(0.0080 ± 0.0023)/DR instead of Δn = (0.044 ± 0.001)–(0.0048 ± 0.0014)/DR. Orientation increases up to DR 3; however, the claim that orientation increases up to DR 5 remains consistent with the data within statistical significance. The deformation remains consistent with the Kratky II limiting case due to the gradual nonlinear nature of the change of orientation and there is no need to modify this conclusion.
In section “Effects of the aspect ratio of the spinneret and guide-to-godet stress,” the new s = 1.17 ± 0.05 instead of 1.95 ± 0.08. The conclusions remain intact.
The correct DRs in Table 1 are:
DR reported
DR
1
0.6
3
1.8
7.5
4.5
In section “Conclusions,” the claim that Kong and Eichhorn claim a dependency on DR−0.5 is incorrect: They claim a dependency ds−0.5 on the fiber diameter ds, which is equivalent to our claim of DR−1.

Copyright information

© Springer Science+Business Media Dordrecht 2017
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https://link.springer.com/article/10.1007/s10570-017-1305-y

Chavicol benzoxazine: Ultrahigh Tg biobased thermoset with tunable extended network

Published Date
Received 2 May 2016, Revised 21 June 2016, Accepted 23 June 2016, Available online 25 June 2016.

Author
Ludovic Dumas. Author links open the author workspace.Opens the author workspaceOpens the author workspacea. Numbers and letters correspond to the affiliation list. Click to expose these in author workspaceb. Numbers and letters correspond to the affiliation list. Click to expose these in author workspaceLeïla Bonnaud. Author links open the author workspace.a. Numbers and letters correspond to the affiliation list. Click to expose these in author workspaceMarjorie Olivier. Author links open the author workspace.b. Numbers and letters correspond to the affiliation list. Click to expose these in author workspaceMarc Poorteman. Author links open the author workspace.b. Numbers and letters correspond to the affiliation list. Click to expose these in author workspacePhilippe Dubois. Author links open the author workspace.a. Numbers and letters correspond to the affiliation list. Click to expose these in author workspace
a
Laboratory of Polymeric and Composite Materials, Center of Innovation and Research in Materials and Polymers (CIRMAP), Materia Nova Research Center & University of Mons, 23 Place du Parc, B-7000 Mons, Belgium
b
Department of Materials Science, Materials Engineering Research Center (CRIM), University of Mons, 23 Place du Parc, B-7000 Mons, Belgium

Highlights

Robust synthesis of a bio based bis-benzoxazine.
Allyl functionalized benzoxazine.
Tunable extended network.
Excellent thermomechanical properties.

Abstract

A novel biobased benzoxazine monomer containing additional allyl functionality was synthesized using a solventless approach from the reaction of a natural occuring phenol: chavicol, para-phenylene diamine and formaldehyde. The chemical structure of this functionalized benzoxazine monomer was confirmed by 1H NMR and FTIR. Its polymerization was investigated and monitored by DSC showing two well defined exotherms allowing the selective ring-opening polymerization of benzoxazine functions and the preservation of the allyl functionality. The network crosslink density could be further increased via the controlled polymerization of allyl functionalities with a post-cure in order to adjust the thermo-mechanical properties. When both networks were polymerized, the thermoset presented an excellent thermo-mechanical stability with a Tα higher than 350 °C as measured by DMTA. This exceptional behavior for a potentially biobased benzoxazine resin will allow the preparation of sustainable high performance biocomposite materials.
For further details log on website :
http://www.sciencedirect.com/science/article/pii/S001430571630355X

High temperature, flame-retardant, and transparent epoxy thermosets prepared from an acetovanillone-based hydroxyl poly(ether sulfone) and commercial epoxy resins

Published Date
Received 12 November 2015, Revised 29 April 2016, Accepted 14 May 2016, Available online 15 May 2016.

Author
Ching Hsuan Lin. Author links open the author workspace.Opens the author workspaceOpens the author workspaceYu Chun Chou. Author links open the author workspace.Wei Feng Shiao. Author links open the author workspace.Meng Wei Wang. Author links open the author workspace.
Department of Chemical Engineering, National Chung Hsing University, Taichung, Taiwan

Abstract

A phosphinated biphenol, 6-(1-(4-hydroxy-3-methoxyphenyl)-1-(4-hydroxyphenyl)ethyl)-6H-dibenzo[c,e] [1,2]oxaphosphinine 6-oxide (1), was synthesized from a sustainable phenol, acetovanillone. A methoxy-substituted poly(ether sulfone), methoxy-PES-1, was successfully prepared by the nucleophilic substitution of (1) and difluorodiphenyl sulfone in the presence of potassium carbonate. Another phosphinated biphenol, 6-((4-hydroxy-3-methoxyphenyl)(4-hydroxyphenyl)methyl)-6H-dibenzo[c,e] [1,2]oxaphosphinine 6-oxide (2), was prepared from another sustainable phenol, vanillin. However, the preparation of the methoxy-substituted poly(ether sulfone) based on biphenol (2) is not successful due to the biphenol (2) being unstable in an alkaline condition. After demethylation of the methoxy-PES-1, a phenolic hydroxyl poly(ether sulfone), hydroxyl-PES-1, was obtained. The phenolic hydroxyl linkages of the hydroxyl-PES-1 act as reacting sites for the epoxy resins. High-performance, bendable, flame retardant, and unexpectedly transparent cured epoxy film can be achieved through the curing of hydroxyl-PES-1 with commercially-available epoxy resins.

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http://www.sciencedirect.com/science/article/pii/S0032386116304244

Nanofiber diameter in electrospinning of polymer solutions: Model and experiment

Published Date
Received 7 January 2016, Revised 15 May 2016, Accepted 18 May 2016, Available online 20 May 2016.

Author
R. Stepanyan. Author links open the author workspace.Opens the author workspaceOpens the author workspacea. Numbers and letters correspond to the affiliation list. Click to expose these in author workspaceA.V. Subbotin. Author links open the author workspace.b. Numbers and letters correspond to the affiliation list. Click to expose these in author workspaceL. Cuperus. Author links open the author workspace.a. Numbers and letters correspond to the affiliation list. Click to expose these in author workspaceP. Boonen. Author links open the author workspace.a. Numbers and letters correspond to the affiliation list. Click to expose these in author workspaceM. Dorschu. Author links open the author workspace.a. Numbers and letters correspond to the affiliation list. Click to expose these in author workspaceF. Oosterlinck. Author links open the author workspace.a. Numbers and letters correspond to the affiliation list. Click to expose these in author workspaceM.J.H. Bulters. Author links open the author workspace.a. Numbers and letters correspond to the affiliation list. Click to expose these in author workspace
a
Materials Science Center, DSM Research, PO Box 18, NL-6160 MD Geleen, The Netherlands
b
A. V. Topchiev Institute of Petrochemical Synthesis, Russian Academy of Sciences, Moscow 119991, Russia

Highlights

A model for nanofiber formation in electrospinning of polymer solutions is proposed.
Fiber elongation and thinning is driven by electrostatic forces.
It is opposed by viscous forces, enhanced by solvent evaporation.
Diameter is mainly influenced by solution viscosity, evaporation rate and current.
The model predictions are in a good agreement with experiments on polyamide-6.

Abstract

A model describing nanofiber formation in electrospinning of a polymer solution is proposed. It is shown that the final nanofiber diameter is determined by the dynamics governed by two main competing factors: (i) elongation under the influence of the electric repulsion between the charges on the fiber surface, which is opposed by (ii) the viscoelastic forces growing in the course of time due to evaporation and stopping the fiber elongation and thinning. Both scaling and numerical analyses performed show that the terminal fiber diameter is controlled by the solution viscosity, the specific charge (electric current divided by the spinning throughput) and the evaporation rate. Model predictions are supported well by our own experiments performed on polyamide-6 solutions as well as literature data.
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http://www.sciencedirect.com/science/article/pii/S0032386116304359

Synthesis of an intrinsically flame retardant bio-based benzoxazine resin

Published Date 
Received 28 February 2016, Revised 6 May 2016, Accepted 19 May 2016, Available online 20 May 2016.

Author

Hongqiang Yan. Author links open the author workspace.Opens the author workspaceOpens the author workspacea. Numbers and letters correspond to the affiliation list. Click to expose these in author workspaceChuang Sun. Author links open the author workspace.a. Numbers and letters correspond to the affiliation list. Click to expose these in author workspaceZhengping Fang. Author links open the author workspace.a. Numbers and letters correspond to the affiliation list. Click to expose these in author workspaceXiaoqing Liu. Author links open the author workspace.b. Numbers and letters correspond to the affiliation list. Click to expose these in author workspaceJin Zhu. Author links open the author workspace.b. Numbers and letters correspond to the affiliation list. Click to expose these in author workspaceHao Wang. Author links open the author workspace.c. Numbers and letters correspond to the affiliation list. Click to expose these in author workspace
a
Lab of Polymer Material and Engineering, Ningbo Institute of Technology, Zhejiang University, Ningbo, Zhejiang 315100, China
b
Ningbo Key Laboratory of Polymer Materials, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences Institution, Ningbo, Zhejiang 315201, China
c
Centre of Excellence in Engineered Fibre Composites (CEEFC), University of Southern Queensland, Toowoomba, Queensland 4350, Australia

Highlights

An intrinsically flame retardant bio-based benzoxazine (DPA-PEPA-boz) was synthesized from renewable diphenolic acid.
The residual char of P-DPA-PEPA-boz after 400 °C was much higher than those of P-DPA-boz and P-MDP-boz under nitrogen and air atmospheres.
P-DPA-PEPA-boz had a limiting oxygen index (LOI) of 33.5% and achieved V0 level in UL94 test.
Thus, this study demonstrates the great potentials of the intrinsically flame retardant bio-based benzoxazine (DPA-PEPA-boz) in the application of high performance matrix resin and composite material.

Abstract

An intrinsically flame retardant bio-based benzoxazine (diphenolic acid pentaerythritol caged phosphate benzoxazine, DPA-PEPA-Boz) monomer was synthesized from bio-based diphenolic acid (DPA) using a four-step process. The monomer of DPA-PEPA-Boz was characterized by FT-IR, 1H NMR and 13C NMR. The curing behavior of DPA-PEPA-boz was studied and compared with those of DPA based benzoxazine (DPA-Boz) and DPA ester derivative (MDP) based benzoxazine (MDP-Boz) without PEPA by means of non-isothermal differential scanning calorimetry. The results indicated that DPA-PEPA-Boz system showed a two-stage curing, assigned to the exothermic opening reactions of oxazine rings and P–O–C ring in PEPA respectively, while the DPA-Boz and MDP-Boz showed a one-stage curing. In addition, the effect of the introduction of PEPA on thermal and inflammable properties of the resin was evaluated. The residual char of the cured DPA-PEPA-Boz (P-DPA-PEPA-Boz) after 400 °C was much higher than those of cured DPA-Boz (P-DPA-Boz) and cured MDP-Boz (P-MDP-Boz) under nitrogen and air atmospheres. Meanwhile, total heat release (THR), peak heat release rate (PHRR) and heat release capacity (HRC) of P-DPA-PEPA-Boz were about half of those of P-DPA-Boz and P-MDP-Boz. P-DPA-PEPA-Boz had a limiting oxygen index (LOI) of 33.5% and achieved V0 rating in UL94 test. P-DPA-PEPA-Boz behaved as a very good intrinsic thermal and flame retardant bio-based benoxazine resin.

Graphical abstract

An intrinsically flame retardant bio-based benzoxazine (DPA-PEPA-boz) has been synthesized and behaved as a very good intrinsic thermal stable and flame retardant bio-based benzoxazine resin.

Unlabelled figure

For further details log on website :
http://www.sciencedirect.com/science/article/pii/S0032386116304438

Adhesion of Polymers

Published Date
Received 25 June 2008, Revised 20 April 2009, Accepted 27 April 2009, Available online 28 May 2009.

Author
Firas Awaja. Author links open the author workspace.Opens the author workspaceOpens the author workspacea. Numbers and letters correspond to the affiliation list. Click to expose these in author workspaceMichael Gilbert. Author links open the author workspace.b. Numbers and letters correspond to the affiliation list. Click to expose these in author workspaceGeorgina Kelly. Author links open the author workspace.a. Numbers and letters correspond to the affiliation list. Click to expose these in author workspaceBronwyn Fox. Author links open the author workspace.a. Numbers and letters correspond to the affiliation list. Click to expose these in author workspacePaul J. Pigram. Author links open the author workspace.b

a
Centre for Material and Fibre Innovation, Geelong Technology Precinct, Deakin University, Geelong, Victoria 3217, Australia
b
Centre for Materials and Surface Science and Department of Physics, La Trobe University, Victoria 3086, Australia

Abstract

Most industrially applied polymer resins and composites have low surface free energy and lack polar functional groups on their surface, resulting in inherently poor adhesion properties. A strong research momentum to understand polymer adhesion in the last decade has been motivated by the growing needs of the automotive and aerospace industries for better adhesion of components and surface coatings. This paper reviews the recent research efforts on polymer adhesion with a special focus on adhesion mechanisms. It starts with an introduction to adhesion with explanatory notes on adhesion phenomena. Recent research on the adhesion mechanisms of mechanical coupling, chemical bonding and thermodynamic adhesion is then discussed. The area of adhesion promoters is reviewed with the focus on plasma and chemical treatments, along with direct methods for adhesion measurement. The topics of polymer blends and reactive polymerization are considered and the interactions with adhesion mechanisms are reported. The concluding section provides recommendations regarding future research on the contentious aspects of currently accepted adhesion mechanisms and on strategies for enhancing polymer adhesion strength.
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http://www.sciencedirect.com/science/article/pii/S0079670009000501

Microwave-assisted synthesis and high-performance anhydrous electrorheological characteristic of monodisperse poly(ionic liquid) particles with different size of cation/anion parts

Published Date
Received 28 March 2016, Revised 12 May 2016, Accepted 19 May 2016, Available online 20 May 2016

Author
Yuezhen Dong. Author links open the author workspace.Jianbo Yin. Author links open the author workspace.Opens the author workspaceOpens the author workspaceJinhua Yuan. Author links open the author workspace.Xiaopeng Zhao

Smart Materials Laboratory, Department of Applied Physics, Northwestern Polytechnical University, Xi’an, 710129, People’s Republic of China

Highlights

Monodisperse PIL particles with different size of anion/cation parts are synthesized.
The PIL particles show strong anhydrous ER characteristic under electric fields.
The ER characteristic of PIL particles depends on the size of cation/anion parts.
The strong ER effect is attributed to the interfacial polarization of PIL particles.
The interfacial polarizability of PILs is related to the size of cation/anion parts.
Abstract

Monodisperse poly(ionic liquid) particles with a styrenic backbone and different size of quaternary ammonium/fluorinated imide ion parts were synthesized by microwave-assisted dispersion polymerization for use as high-performance anhydrous polyelectrolyte-based smart electrorheological materials. The morphology and structure of particles were characterized by SEM, NMR, FT-IR, and TGA. The electrorheological effect of poly(ionic liquid) particles in silicone oil was investigated by rheometer under electric fields. It showed that, different from classic polyelectrolytes, the poly(ionic liquid) particles possess strong electrorheological effect in dry state and the electrorheological effect depends on the size of cation/anion parts. The poly(ionic liquid) particles having smaller cation/anion parts possess stronger electrorheological effect. Dielectric analysis indicated that the local ion motion-induced interfacial polarization is responsible for the strong electrorheological effect of poly(ionic liquid) particles and the dependence of electrorheological effect on the size of cation/anion is related to the change of interfacial polarizability with the size of cation/anion parts.

Graphical abstract

By a microwave-assisted dispersion polymerization, monodisperse poly(ionic liquid) particles with a styrenic backbone and different size of quaternary ammonium/fluorinated imides ion parts are synthesized. Under electric fields, the poly(ionic liquid) particles possess strong electrorheological effect in the absence of water activator and the electrorheological effect depends on the size of cation/anion parts.
Unlabelled figure

For further details log on website :
http://www.sciencedirect.com/science/article/pii/S0032386116304426

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