Preparation and characterization of thermoplastic starch/zein blends
01 Sep 2007-Materials Research-ibero-american Journal of Materials (Materials Research)-Vol. 10, Iss: 3, pp 227-231
TL;DR: The use of zein in thermoplastic starch compositions causes a decrease in the water sensitivity of these materials and lower its melt viscosity during processing making zein a suitable and very promising component in TPS compositions as mentioned in this paper.
Abstract: Blends of starch and zein plasticized with glycerol were prepared by melting processing in an intensive batch mixer connected to a torque rheometer at 160 °C. The resulting mixtures were compression molded and then characterized by scanning electron microscopy, differential scanning calorimetry, wide-angle X ray diffraction and water-absorption experiments. The blends were immiscible, showing two distinct phases of starch and zein. The water uptake at equilibrium and its diffusion coefficient were determined. The water uptake at equilibrium decreased with increasing zein content. The diffusion coefficient fell sharply on addition of 20% zein and remained constant as zein content was increased. No appreciable effect of zein on starch crystallization was observed by X ray diffraction. The use of zein in thermoplastic starch compositions causes a decrease in the water sensitivity of these materials and lower its melt viscosity during processing making zein a suitable and very promising component in TPS compositions.
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TL;DR: In this paper, a number of cellulose/iron oxide hybrid pigments for thermoplastic starch (TPS) based products were used for the production of materials with good dispersion and strong adhesion.
Abstract: Cellulose/iron oxide hybrids were prepared by the controlled hydrolysis of FeC2O4 in the presence of vegetable and bacterial cellulose fibres as substrates. By varying the relative amount of FeC2O4 and NaOH, either hematite or magnetic iron oxides were grown at the cellulose fibres surfaces. This chemical strategy was used for the production of a number of materials, whose coloristic properties associated to their reinforcement role allowed their use as new hybrid pigments for thermoplastic starch (TPS) based products. The TPS reinforced materials were characterized by several techniques in order to evaluate: the morphology and the compatibility between the matrix and the fillers; the mechanical reinforcement effect of the cellulose/iron oxide pigments on TPS and the coloristic properties of the composites. All materials showed good dispersion and strong adhesion for the cellulose/iron oxide nanocomposites in the TPS matrix thus resulting in improved mechanical properties.
6 citations
01 Jan 2014
TL;DR: In this paper, the degradability of starch-based bio-plastic is checked with microbial Spp in MMSB medium during the process of thermal processing of starch.
Abstract: Bio-Plastic are a form of plastic derived from rene wable biomass source such as vegetable fats, oils and cornstarch, pea starch or micro biot a. Thermo starch Plastic currently represents the most widely used bio-plastic pure starch posses ses the characteristics of being able to absorb humidity and thus is it being used for the p roduction of drug capsule in pharmaceutical sector. Bio-plastic can be made from a compound Polyhydroxyalkanotes (PHA) and Polyhydxoxybutyrate (PHB) was synthesized from acetyl Co-A. For the production of starch based plastic, glycerol was added for the gelatiniz ation of starch during thermal processing. Check their degradability with microbial Spp in MMSB medium during this study. This starch based plastic can be used in Medical, Agriculture a nd food packing .
5 citations
TL;DR: It is proposed that a key indicator of foamability is the strain at break of the materials to be foamed (as calculated from stress vs. strain rate curves) and zein foams exhibit attractive properties (average pore size, poresize distribution, and porosity) for cell culture applications.
Abstract: Background Foams are high porosity and low density materials In nature, they are a common architecture Some of their relevant technological applications include heat and sound insulation, lightweight materials, and tissue engineering scaffolds Foams derived from natural polymers are particularly attractive for tissue culture due to their biodegradability and bio-compatibility Here, the foaming potential of an extensive list of materials was assayed, including slabs elaborated from whole flour, the starch component only, or the protein fraction only of maize seeds Methodology/Principal Findings We used supercritical CO 2 to produce foams from thermoplasticized maize derived materials Polyethylene-glycol, sorbitol/glycerol, or urea/formamide were used as plasticizers We report expansion ratios, porosities, average pore sizes, pore morphologies, and pore size distributions for these materials High porosity foams were obtained from zein thermoplasticized with polyethylene glycol, and from starch thermoplasticized with urea/formamide Zein foams had a higher porosity than starch foams (88% and 85%, respectively) and a narrower and more evenly distributed pore size Starch foams exhibited a wider span of pore sizes and a larger average pore size than zein (20884 vs 5543 μm2, respectively) Proof-of-concept cell culture experiments confirmed that mouse fibroblasts (NIH 3T3) and two different prostate cancer cell lines (22RV1, DU145) attached to and proliferated on zein foams Conclusions/Significance We conducted screening and proof-of-concept experiments on the fabrication of foams from cereal-based bioplastics We propose that a key indicator of foamability is the strain at break of the materials to be foamed (as calculated from stress vs strain rate curves) Zein foams exhibit attractive properties (average pore size, pore size distribution, and porosity) for cell culture applications; we were able to establish and sustain mammalian cell cultures on zein foams for extended time periods © 2015 Trujillo-de Santiago et al
5 citations
Cites methods from "Preparation and characterization of..."
...Preliminary experiments were conducted to find suitable processing conditions for each composition, starting from values reported for similar materials [35,36,44,47]....
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Journal Article•
TL;DR: In this article, a mixture of polypropylene and thermoplastic starch is modified by eggshell nano-particles and mechanical property of the prepared samples is investigated through break point and young modulus tests.
Abstract: Starch as an inexpensive and renewable source is used as a filler in plastics industry for about two decades. In current study, the blend of polypropylene and thermoplastic starch is modified by eggshell nano-particles and mechanical property of the prepared samples is investigated through break point and young modulus tests. In order to improve the compatibility between hydrophilic starch and polypropylene, of maleic anhydride and ethylene vinyl acetate are used as a compatibilizer to enhance the dispersion and the interfacial affinity in thermoplastic starch and polypropylene blend. Then the biodegradability and surface morphology of prepared samples is studied considering weight loss, FTIR and SEM tests. Mechanical results showed that strain at break point and Young’s modulus specifications are improved in the prepared samples. The results showed that adding starch to polypropylene increases biodegradability and results lower hydroxyl groups in prepared sample.
5 citations
Cites background from "Preparation and characterization of..."
...studied effect of zein on properties of starch and glycerol blend [9]....
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01 Sep 2018
TL;DR: In this article, the authors developed and characterized nano-filler reinforced thermoplastic starch (TPS) composites and found that the degradation rate of composites are slow and lost only on an average of 45% of their original weight after 60 days under soil burial condition.
Abstract: The aim of the present investigation is to develop and characterize nano-filler reinforced thermoplastic starch (TPS) composites. Both montmorillonite (MMT), and Cloisite 30B are used in different weight percentages as reinforcing filler with TPS by hot compression molding to develop starch-mmt (SM) and starch-cloisite (SC) composites respectively. Fabricated composites were mechanically tested. Composite containing 3 wt% mmt showed tensile strength and tensile modulus of 2.67 MPa and 68.4 MPa respectively X-ray diffraction (XRD) and transmission electron microscopy (TEM) of nano-composites were analyzed. Biodegradation of composites were carried out in soil burial condition for certain time periods and found that the degradation rate of composites are slow and lost only on an average of 45% of their original weight after 60 days under soil burial condition. Surface topography of degraded samples was studied under scanning electron microscope. As SM and SC composites are biodegradable in nature, these can be utilized as packaging materials, molded articles and other aesthetic products to reduce the use of non degradable synthetic plastic.
5 citations
References
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Book•
01 Jan 1956
TL;DR: Though it incorporates much new material, this new edition preserves the general character of the book in providing a collection of solutions of the equations of diffusion and describing how these solutions may be obtained.
Abstract: Though it incorporates much new material, this new edition preserves the general character of the book in providing a collection of solutions of the equations of diffusion and describing how these solutions may be obtained
20,495 citations
3,755 citations
TL;DR: The combination of bio-fibers such as kenaf, hemp, flax, jute, henequen, pineapple leaf fiber, and sisal with polymer matrices from both nonrenewable and renewable resources to produce composite materials that are competitive with synthetic composites requires special attention as discussed by the authors.
Abstract: Sustainability, industrial ecology, eco-efficiency, and green chemistry are guiding the development of the next generation of materials, products, and processes. Biodegradable plastics and bio-based polymer products based on annually renewable agricultural and biomass feedstock can form the basis for a portfolio of sustainable, eco-efficient products that can compete and capture markets currently dominated by products based exclusively on petroleum feedstock. Natural/Biofiber composites (Bio-Composites) are emerging as a viable alternative to glass fiber reinforced composites especially in automotive and building product applications. The combination of biofibers such as kenaf, hemp, flax, jute, henequen, pineapple leaf fiber, and sisal with polymer matrices from both nonrenewable and renewable resources to produce composite materials that are competitive with synthetic composites requires special attention, i.e., biofiber–matrix interface and novel processing. Natural fiber–reinforced polypropylene composites have attained commercial attraction in automotive industries. Natural fiber—polypropylene or natural fiber—polyester composites are not sufficiently eco-friendly because of the petroleum-based source and the nonbiodegradable nature of the polymer matrix. Using natural fibers with polymers based on renewable resources will allow many environmental issues to be solved. By embedding biofibers with renewable resource–based biopolymers such as cellulosic plastics; polylactides; starch plastics; polyhydroxyalkanoates (bacterial polyesters); and soy-based plastics, the so-called green bio-composites are continuously being developed.
1,921 citations
TL;DR: In this paper, the composites were conditioned at various moisture contents in order to evaluate the effect of amylopectin on the composite structure, and the resulting films were characterized using scanning electron microscopy, differential scanning calorimetry, water absorption experiments, and wide-angle X-ray scattering.
Abstract: Nanocomposite materials were obtained using glycerol plasticized starch as the matrix and a colloidal suspension of cellulose whiskers as the reinforcing phase. The cellulose whiskers, prepared from tunicin, consisted of slender parallelepiped rods with a high aspect ratio. After mixing the raw materials and gelatinization of starch, the resulting suspension was cast and evaporated under vacuum. The composites were conditioned at various moisture contents in order to evaluate the effect of this parameter on the composite structure. The resulting films were characterized using scanning electron microscopy, differential scanning calorimetry, water absorption experiments, and wide-angle X-ray scattering. An accumulation of plasticizer in the cellulose/amylopectin interfacial zones was evidenced. The specific behavior of amylopectin chains located near the interface in the presence of cellulose probably led to a transcrystallization phenomenon of amylopectin on cellulose whiskers surface.
622 citations
TL;DR: In this article, a review of the early literature on zein is presented, which reexamines the old literature and reconciles it with new zein research to illustrate some of the unique properties of and opportunities for zein.
Abstract: Corn is the largest and most important agricultural commodity in America. Zein, one of the components in corn, has long been investigated for uses other than food and feed. Zein is a unique and complex material, and it is one of the few cereal proteins extracted in a relatively pure form. Today, because of environmental concerns, interest in zein utilization is again growing. Some of the more important research on zein is more than 50 years old. Most of this work has been either forgotten, lost, or difficult to locate. Much of this work was done at the USDA laboratory in Peoria, IL. Since most early zein literature is still easily accessible at that laboratory, this review on zein has been prepared making use of this old literature. This review reexamines the old literature and reconciles it with new zein research to illustrate some of the unique properties of and opportunities for zein.
461 citations