The influence of starch gelatinization on the rheological, thermal, and morphological properties of poly(ɛ-caprolactone) with corn starch blends

Purpose This study aims to develop a biodegradable linear low-density polyethylene (LLDPE)/starch blends with improved mechanical and flow characteristics and evaluate the probability of using essential oils such as Moringa oleifira and castor oils as green plasticizers and compatibilizers to avoid using harmful chemicals. Design/methodology/approach Corn starch was blended with LLDPE through the melt blending technique. The corn starch content was varied from 5 to 40 phr in LLDPE. To enhance poor mechanical characteristic of the LLDPE/starch, essential oils such as M. oleifira and castor oils were incorporated into the composites with different concentrations starting from 1 to 7 phr. The essential oils’ effect on mechanical, flow character, thermal stability and electrical properties of the LLDPE/starch was also investigated. The morphology of LLDPE/starch containing essential oils was also investigated by scanning electron microscope (SEM). Findings The results revealed that increasing the corn starch content had an adverse effect on mechanical and flow characteristics of the composites, whereas incorporation of essential oils had increased the flow and mechanical characteristics of the composites. Also, dielectric measurements revealed that permittivity and dielectric loss increased by increasing oil content. Moreover, the values of the blends containing castor oil are higher compared to that containing M. oleifira. The SEM micrographs illustrated that the presence of essential oils in LLDPE/starch enhanced the distribution and the homogeneity of the composites, and the particle size of starch granules became smaller in LLDPE matrix. Originality/value This study aims to introduce green plasticizer and compatibilizer to avoid using harmful chemicals in packaging industry.

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Linear Shrinkage, Strength and Porosity of Alumina-Based Ceramic Foam with Corn Starch as Pore Former

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.317.75 ◽

2021 ◽

Vol 317 ◽

pp. 75-80

Author(s):

Nurul Farhana Abdul Rahman ◽

Hamimah Abdul Rahman ◽

Wan Muhammad Syahmi Wan Azhan ◽

Nor Hamidah Yatim

Keyword(s):

Flexural Strength ◽

Corn Starch ◽

Total Porosity ◽

Linear Shrinkage ◽

Ceramic Foam ◽

Morphological Properties ◽

Pore Former ◽

Ceramic Foams ◽

Dispersing Agent ◽

Suitable Amount

In this study, ceramic foams were produced using starch consolidation casting method. This research focused on the preparation of alumina-based ceramic foam by using corn starch as a pore-forming agent. Preparation of alumina based ceramic foam is studied to observe the effect of the addition of corn starch on its physical, mechanical and morphological properties. The composition of the suspension used included 64–58 wt.% alumina, 55 wt.% deionised water and other materials, such as silica and polyethylene glycol (PEG), were used as additive and dispersing agent respectively. Corn starch was added at 4, 6, 8 and 10 wt.%. The samples were preheated for gelation and coagulation processes, then dried and sintered at 1250 °C for 2 h. The ceramic foam gave a linear shrinkage from 1.07% to 3.39%. The obtained flexural strength was between 0.594 and 1.996 MPa. The average total porosity ranged from 54.05% to 70.70%. This study found that the suitable amount of corn starch in alumina foam is 4 wt.% because the resulting porosity values and flexural strength are appropriate for ceramic foams.

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