Evaluation of physicochemical properties of film-based alginate for food packing applications

Abstract The indiscriminate use of films as synthetic primary packaging, for the conservation and transport of fruit and vegetable products in postharvest, causes disposal problems. In the present work, films based on sodium alginate were synthesized and characterized, with alginate as a biopolymer matrix, glycerol (plasticizer), oleic acid (control of hydrophilicity), and calcium chloride (cross-linking agent). The dynamic mechanical, thermal, structural, and hydrophobicity properties were studied. In the case of dynamic mechanical properties, they were analyzed at a temperature of −50°C, because food packaging goes through storage during its cold chain, showing biofilm stability under these conditions. On the other hand, infrared spectroscopy analysis showed that the carboxylate and carboxy functional groups serve as a link for all the components, and oleic acid is also serving as a plasticizer and, to a lesser degree, as a hydrophilicity controller.

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Effect of Cross-Linking Density on Dynamic Mechanical Properties of Polynorbornen Compounds.

KOBUNSHI RONBUNSHU ◽

10.1295/koron.53.465 ◽

1996 ◽

Vol 53 (8) ◽

pp. 465-471 ◽

Cited By ~ 1

Author(s):

Saburou KUBOTA

Keyword(s):

Mechanical Properties ◽

Dynamic Mechanical Properties ◽

Cross Linking ◽

Dynamic Mechanical

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Sulfonated Polystyrene Ionomers Neutralized with Mixtures of Various Cations Studied by Dynamic Mechanical and Small-Angle X-Ray Scattering Techniques

MRS Proceedings ◽

10.1557/proc-778-u3.8 ◽

2003 ◽

Vol 778 ◽

Author(s):

Ho Seung Jeon ◽

Ju-Myung Song ◽

Joon-Seop Kim

Keyword(s):

Glass Transition ◽

Dynamic Mechanical Properties ◽

The Other ◽

Transition Temperatures ◽

Glass Transition Temperatures ◽

Dynamic Mechanical ◽

The Matrix ◽

Cluster Phase ◽

The One ◽

Zinc Cations

AbstractThe effects of the addition of mixed cations, i.e. Na+/Cs+, Ba2+/Cs+, and Ba2+/Zn2+, to the acid form sulfonated styrene copolymers on their dynamic mechanical properties and morphology were investigated. It was found that the matrix glass transition temperatures did not change with the ratio of the one cation to the other. As expected, however, the ratio of one cation to the other in the mixed cations affected cluster glass transition temperatures significantly. It was also found that the activation energies for the glass transitions for the matrix phase remained constant, while those for the cluster phase changed with the ratio of the two cations. In addition, the position of the SAXS peak was found to be affected by the type of cations. From the results obtained above, the decrease in the cluster Tg with increasing the amount of cesium and zinc cations in Na/Cs, Ba/ Cs, and Ba/Zn mixtures, were explained on the basis of the considerations of the size, charge, and type of cations, which alter the degree of clustering as well as ion-hopping mechanism.

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Effect of cross-linking agents on the dynamic mechanical properties of hydrogel blends of poly(acrylic acid)-poly(vinyl alcohol-vinyl acetate)

Biomaterials ◽

10.1016/0142-9612(96)00058-0 ◽

1996 ◽

Vol 17 (23) ◽

pp. 2259-2264 ◽

Cited By ~ 39

Author(s):

J Cauich-Rodriguez

Keyword(s):

Mechanical Properties ◽

Acrylic Acid ◽

Vinyl Acetate ◽

Vinyl Alcohol ◽

Dynamic Mechanical Properties ◽

Poly Vinyl Alcohol ◽

Cross Linking ◽

Dynamic Mechanical ◽

Poly Acrylic Acid

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The Effect of Cross-Linking on the Dynamic Mechanical Properties of an Incompatible, Segmented Polyurethane

Polymer Alloys ◽

10.1007/978-1-4684-0874-4_19 ◽

1977 ◽

pp. 299-312

Author(s):

J. L. Work ◽

J. E. Herweh ◽

C. A. Glotfelter

Keyword(s):

Mechanical Properties ◽

Dynamic Mechanical Properties ◽

Cross Linking ◽

Segmented Polyurethane ◽

Dynamic Mechanical

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Temperature Dependent Dynamic Mechanical Properties of Hydrogenated Nitrile Butadiene Rubber and the Effect of Peroxide Cross-linkers

e-Polymers ◽

10.1515/epoly.2007.7.1.1536 ◽

2007 ◽

Vol 7 (1) ◽

Cited By ~ 1

Author(s):

Blaž Likozar ◽

Matjaž Krajnc

Keyword(s):

Mechanical Properties ◽

Cyano Group ◽

Viscoelastic Behavior ◽

Dynamic Mechanical Properties ◽

Cross Linking ◽

Butadiene Rubber ◽

Scanning Calorimetry ◽

Dynamic Mechanical ◽

Nitrile Butadiene Rubber ◽

The Cross

AbstractThe viscoelastic behavior of hydrogenated nitrile butadiene rubber (HNBR) was studied over a range of temperatures and shear frequencies. Dynamic mechanical properties were studied and modelled using the generalized Maxwell model and the Williams-Landel-Ferry equation. A fitting algorithm was developed to provide the best agreement between the experimental data and the model results. In addition to dynamic mechanical analysis (DMA), differential scanning calorimetry (DSC) was applied. The HNBR structure was characterized by X-ray diffraction (XRD). The developed model exhibited an excellent agreement with either isothermal or dynamic experiment data, yet only up to the rubbery plateau, after which a structure ordering occurred. This was explained by the cyano group secondary bonding and consequentially the cross-linking between HNBR chains. A molecular modeling simulation was made to confirm the cross-linking. The effect of peroxide cross-linking agents in a compound resembled the one usually observed in the filler formulated compounds.

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