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One engine that drives the United States’ economic growth is an ever-increasing demand for manufactured products, both at home and abroad. This increase has created a major concern for the environment in terms of disposing used goods and ensuring that these products are safe. As environmental concerns grow, however, renewable resources are gaining increasing attention, especially as industrial ecology and product biodegradability gain importance. Added to this, biological materials are increasingly being utilized to replace traditional materials in manufacturing. To aid both educators as well as researchers, this paper examines several considerations that are essential for manufacturing plastic products that contain biomaterials. These include the selection of materials, the selection of manufacturing processes, manufacturing costs, and the quality of final products. Additionally, several standard methods that are commonly used for the determination of mechanical and physical properties are compiled; thus this paper should be a useful resource for both educators and researchers. The trends discussed here and their implications are critical for those involved in manufacturing, because contrary to conventional wisdom, simultaneously meeting the material production needs of our society, as well as that of the environment are not mutually-exclusive. 相似文献
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Vanessa Cheesbrough Kurt A. Rosentrater Jerry Visser 《Journal of Polymers and the Environment》2008,16(1):40-50
Interest in renewable biofuel sources has intensified in recent years, leading to greatly increased production of ethanol
and its primary coproduct, Distillers Dried Grain with Solubles (DDGS). Consequently, the development of new outlets for DDGS
has become crucial to maintaining the economic viability of the industry. In light of these developments, this preliminary
study aimed to determine the suitability of DDGS for use as a biofiller in low-cost composites that could be produced by rapid
prototyping applications. The effects of DDGS content, particle size, curing temperature, and compression on resulting properties,
such as flexural strength, modulus of elasticity, water activity, and color were evaluated for two adhesive bases. The composites
formed with phenolic resin glue were found to be greatly superior to glue in terms of mechanical strength and durability:
resin-based composites had maximum fiber stresses of 150–380 kPa, while glue composites had values between 6 kPa and 35 kPa;
additionally, glue composites experienced relatively rapid microbial growth. In the resin composites, both decreased particle
size and increased compression resulted in increased mechanical strength, while a moderate DDGS content was found to increase
flexural strength but decrease Young’s modulus. These results indicate that DDGS has the potential to be used in resin glue-based
composites to both improve flexural strength and improve potential biodegradability. 相似文献
3.
David D. Cornell 《Journal of Polymers and the Environment》2007,15(4):295-299
The existing plastic bottle reclaiming industry has working technology, satisfied customers, raw material, and investors.
Adding new materials to the current mix requires satisfying all four needs for those materials. Rigid plastic container recycling
focuses on high-density polyethylene (HDPE) and polyethylene terephthalate (PET) bottles, the overwhelming percentage of bottles
sold in North America. Bottles of other resins, including polyvinyl chloride (PVC), polypropylene and biopolymers, lack critical
mass necessary for independent reclamation. To be mechanically recycled, biopolymers must be either completely fungible with
existing recycled resins or be available in sufficient quantity to achieve the needed critical mass. So far, biopolymer volume
projections are not encouraging. Biopolymers, like all minor bottle resins, must pay their own way in sorting and processing
without subsidy from PET and HDPE recycling. Based on limited data, some biopolymers may have little effect on recycled HDPE
performance, but will represent a yields loss and added economic burden at some level of occurrence. Biopolymers have not
been shown to be compatible with PET and likely will represent performance problems and economic burdens at even low levels
of occurrence. Applications for biopolymers should be carefully selected so as to not interfere with currently recycled materials
unless critical mass can be achieved quickly.
相似文献
David D. CornellEmail: |
4.
Long Jiang Jijun Huang Jun Qian Feng Chen Jinwen Zhang Michael P. Wolcott Yawei Zhu 《Journal of Polymers and the Environment》2008,16(2):83-93
In this study, poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV)/bamboo pulp fiber (BPF) composites were prepared by melt compounding and injection molding. The
crystallization ability, tensile strength and modulus, flexural strength and modulus, and impact strength were found substantially
increased by the addition of BPF. Tensile and flexural elongations were also moderately increased at low fiber contents (<20%).
BPF demonstrated not only higher strength and modulus, but also higher failure strain than the PHBV8 matrix. Boron nitride
(BN) was also investigated as a nucleation agent for PHBV8 and maleic anhydride grafted PHBV8 (MA-PHBV8) as a compatibilizer
for the composite system. BN was found to increase the overall properties of the neat polymer and the composites due to refined
crystalline structures. MA-PHBV8 improved polymer/fiber interactions and therefore resulted in increased strength and modulus.
However, the toughness of the composites was substantially reduced due to the hindrance to fiber pullout, a major energy dissipation
source during the composite deformation. 相似文献
5.
R. A. Tatara S. Suraparaju K. A. Rosentrater 《Journal of Polymers and the Environment》2007,15(2):89-95
With the rapid growth in the ethanol fuel industry in recent years, considerable research is being devoted to optimizing the
use of processing coproducts, such as distillers dried grains with solubles (DDGS), in livestock diets. Because these residues
contain high fiber levels, they may be amendable to incorporation into bio-based composites. Thus, the goal of this study
was to demonstrate the viability of using corn-based DDGS as a biofiller with phenolic resin, in order to produce a novel
biomaterial. DDGS was blended with phenolic resin at 0, 10, 25, 50, 75, and 90%, by weight, and then compression molded at
51 MPa (3.7 tons/in2) and 174 °C (345°F). Molded specimens were then tested for tensile strength. Tensile yield strengths ranged from 32 MPa (4,700 psi)
to 7.6 MPa (1,100 psi), while the engineering strain ranged from 0.6% to 1.25%. Results indicate that DDGS concentrations
between 25% and 50% retained sufficient mechanical strength and thus represent reasonable inclusion values. Additionally,
data were similar to those from other studies that have investigated biofillers. Follow-up studies should quantify the effects
of altering molding parameters, including molding pressure, temperature, and time, as well as pretreatment of the DDGS. Additionally,
strength of the DDGS composites should be optimized through the use of coupling agents or other additives.
Mention of a trade name, proprietary product, or specific equipment does not constitute a guarantee or warranty by the United
States Department of Agriculture and does not imply approval of a product to the exclusion of others that may be suitable. 相似文献
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