preparation of polyurethane acrylate/ organically …2017/04/28 · production of polymers. •...

Preparation of Polyurethane Acrylate/ Organically Modified Montmorillonite Nanocomposites by

Electron Beam Radiation Curing

By

Dr. Ashraf Salih

Sudan Atomic Energy CommissionP. O Box 3001, Khartoum, Sudan

27/04/2017

Introduction

Sudan Atomic Energy Commission

• Polyurethanes (PUs) are hetrochain polymerscharacterized by repeated units contain carbamate(urethane) –NH-CO- groups.

• The continuous elevation in petroleum prices, its impacton the environment, increasing demands for renewable,environmentally friendly source for the industrialproduction of polymers.

• Although the polyurethane acrylate has excellent properties,still it has low modulus and tensile strength. Incorporation oflow amount of clay will enhance the mechanical properties.

4/28/2017 2

Introduction

• Radiation curing is a process of converting liquid prepolymers and monomers into a solid cured films.

• The energy of the UV radiation or the electron beam is used to induce free radical polymerization, and thus curing of the polymer films take place.

• Advantages: can be performed at room temperature, with a fast curing rate, No volatile chemicals.

Sudan Atomic Energy Commission4/28/2017 3

Introduction


• EB has been used in different applications of resin. such asacrylate composites (Vautard et al., 2011), epoxy acrylateresins for conductive films application, curing of thermoset-thermoplastic blend (Alessi et al., 2011), epoxy/claynanocomposites (Khaksari et al., 2013) and polyurethanenanocomposites for coating application (Steele et al., 2012).

• Electron beam radiation was found to be an excellentmethod for the rapid curing without using of chemicalinitiators. Therefore, it is an environmentally friendlytechnique (Alessi et al., 2007b; Mascioni et al., 2013; Sui etal., 2003).

Objective of the Study

To Investigate the electron beam

radiation-induced curing of palm oil

based polyurethane acrylate/clay

nanocomposites.


Experimental


Polyurethane Acrylate (PUA)+ Reactive

monomers

ODA-MMTstirringSonication at 25°C

Casting in Al-mold with thickness≈

1mm

EB Curing with different doses

Coating in glass substrate

thickness≈ 20μm

Experimental


Formula

PUA

(g)

TMPTA

(g)

DPGDA

(g)

Mono-Ac

(g)

Filler (%)

PUA 7.00 0.70 1.40 2.80 0

PUA-ODA-

MMT

7.00 0.70 1.40 2.80 1,3,5, ODA-MMT

PUA-MMT 7.00 0.70 1.40 2.80 1,3,5, Na-MMT

The Typical Formulation of the PUA/ODA-MMT Nanocomposites Films

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Characterization


Morphology

XRD

TEM

Chemical structure FTIR

Mechanical Properties

Tensile

Test

DMA

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Results & Discussion/ FTIR


The nanocomposites spectra displayed an absorption IR bands at 1035 cm-1 (Si-O-Si, Si-O-C) asymmetric stretching vibration, the stretching band of Si-OH at 954 cm-1, Si-O-C deformation at 833 cm-1, Mg-O bending vibration at 515 cm-1, therefore the ODA-MMT was successfully dispersed in the PUA matrix.

4/28/20179

Results & Discussion/ XRD

The distance between the silicate layers was increased due to the intercalation of the PUA chains in the gallery spacing. The microcomposite sample with pristine MMT 5 wt% displayed diffraction peak at 2θ = 7.9° corresponding to d spacing about 11.9 Å, revealing the poor interaction between the pristine MMT and PUA matrix.

4/28/2017 10Sudan Atomic Energy Commission

Results & Discussion/ TEM


TEM micrographs of (A) PUA/MMT 5 wt% at low magnification, (B)PUA/MMT 5 wt% at high magnification, (C) PUA/ODA-MMT 3 wt%, and (D)PUA/ODA-MMT 5 wt%.

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Results & Discussion/ DMA


• The presence of the ODA-MMT in the PUA matrix led to decrease the segmentalmotions, and increase significantly the storage modulus of the PUA in the glassystate.

• E’ values in the rubbery state were lower than in the glassy state.

Results & Discussion/ DMA-Tan δ


• The 3 wt% ODA-MMT led to elevate the Tg value to 65.1°C (From 37.9°C), and no significant change could be found when the amount increased to 5 wt%, (Tgwas about 64.38°C)

Results & Discussion/ Mechanical

Properties


• These results revealed that the stiffness of the PUA was increased by incorporation of the organoclay.

Results & Discussion/ Effect of Radiation

Dose


60

65

70

75

80

85

90

95

0 20 40 60 80 100 120 140 160

Ge

l co

nte

nt

(%)

Radiation dose (kGy)

• The gel fraction in the PUA nanocomposites films increased with the radiation doses.

Results & Discussion/ Effect of TMPTA

Content


50

55

60

65

70

75

80

85

90

95

100

0 10 20 30 40 50

Ge

l c

on

ten

t (%

)

TMPTA amount (%)

• The increase of the TMPTA amount, resulted in a significant increase in the gel fraction in of the PUA nanocomposites films.

Conclusion• EB curing produced nanocomposites, with remarkable

improvement in the thermal, mechanical and morphologicalproperties, compared to the pristine PUA.

• The nanocomposites prepared by Eb showed betterProperties.

• The Young`s modulus increased from 8.53 to 132.43 MPaand the tensile values were also increased significantlyfrom 1.54 to 11.11 MPa.

• The storage modulus value from 17 to 40 MPa, innanocomposites with 3 wt% ODA-MMT nanocomposites.


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Alessi, S., Dispenza, C., Pitarresi, G., & Spadaro, G. (2011). Radiation curing of thermosetting-

thermoplastic blends as matrices for structural carbon fibre composites Advances in

Composite Materials-Ecodesign and Analysis (pp. 125-140). Rijeka: In Tech.

Alessi, S., Dispenza, C., & Spadaro, G. (2007). Thermal Properties of E-beam Cured

Epoxy/Thermoplastic Matrices for Advanced Composite Materials. Macromolecular

Symposia, 247, 238-243.

Khaksari, M., Ahmadi, S. J., Moosaviyan, S. M. A., & Nazeri, M. (2013). Effect of electron beam

irradiation on thermal and mechanical properties of epoxy/clay nanocomposites. Journal of

Composite Materials, 47(28), 3517-3524.

Mascioni, M., Ghosh, N. N., Sands, J. M., & Palmese, G. R. (2013). Electron beam and UV

cationic polymerization of glycidyl ethers – part I: Reaction of monofunctional phenyl

glycidyl ether. Journal of applied polymer science, 130, 479-486. doi: 10.1002/app.39184

Steele, A., Bayer, I., & Loth, E. (2012). Adhesion strength and superhydrophobicity of

polyurethane/organoclay nanocomposite coatings. Journal of applied polymer science,

125(S1), E445-E452.

Sui, G., Zhang, Z.-G., Chen, C.-Q., & Zhong, W.-H. (2003). Analyses on curing process of electron

beam radiation in epoxy resins. Materials Chemistry and Physics, 78, 349-357.

Vautard, F., Fioux, P., Vidal, L., Schultz, J., Nardin, M., & Defoort, B. (2011). Influence of the

carbon fiber surface properties on interfacial adhesion in carbon fiber–acrylate composites

cured by electron beam. Composites Part A: Applied Science and Manufacturing, 42(7), 859-

867.

References

Thank you


preparation of polyurethane acrylate/ organically …2017/04/28 · production of polymers. •...

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