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= Bio-Composites =
= Bio-Composites =
Increased interest has come from reinforcing bio-material polymers with environmentally friendly fibres.  This method has proven to increase strength while maintaining the materials environmental benefits. Natural fibers, such as {{wp|Kenaf}} <ref>Takashi Nishino, Koichi Hirao, Masaru Kotera, Katsuhiko Nakamae, Hiroshi Inagaki “Kenaf reinforced bidegradable composite” <http://scholarsportal.info.proxy.queensu.ca/pdflinks/08101219513403958.pdf></ref> and {{wp|Jute}}<ref>Rowell, Roger M. Biological Systems Engineering Dept., University of Wisconsin.“Potentials for Jute Based Composites”<http://www.fpl.fs.fed.us/documnts/pdf1997/rowel97f.pdf></ref> are embedded in a bio-based polymer which has been proven to increase tensile strength in these materials.    Bio- based polymers are often soy-based and show great promise in the environmentally friendly polymer industry.  The properties of the bio-based polymers alone do not provide enough strength to be useful in a wide variety of applications.  Embedded fibers have increased their usefulness in a large number of applications.  A direct link between the cross linking of fibers within the material and material strength has been observed.
Increased interest has come from reinforcing bio-material polymers with environmentally friendly fibres.<ref name = "biocomp">Biocomposites from natural fibres and biodegradable polymers: Processing, properties and future prospects.<http://cat.inist.fr/?aModele=afficheN&cpsidt=14614859></ref> This method has proven to increase strength while maintaining the materials environmental benefits. Natural fibers, such as {{wp|Kenaf}} <ref>Takashi Nishino, Koichi Hirao, Masaru Kotera, Katsuhiko Nakamae, Hiroshi Inagaki “Kenaf reinforced bidegradable composite” <http://scholarsportal.info.proxy.queensu.ca/pdflinks/08101219513403958.pdf></ref> and {{wp|Jute}}<ref>Rowell, Roger M. Biological Systems Engineering Dept., University of Wisconsin.“Potentials for Jute Based Composites”<http://www.fpl.fs.fed.us/documnts/pdf1997/rowel97f.pdf></ref> are embedded in a bio-based polymer which has been proven to increase tensile strength in these materials.    Bio- based polymers are often soy-based and show great promise in the environmentally friendly polymer industry.  The properties of the bio-based polymers alone do not provide enough strength to be useful in a wide variety of applications.  Embedded fibers have increased their usefulness in a large number of applications.  A direct link between the cross linking of fibers within the material and material strength has been observed.


= Material Efficiency =
= Material Efficiency =
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= Suggestions: The future of PER and PER composite materials =
= Suggestions: The future of PER and PER composite materials =
The promise of bio-composites and PER as PVC alternatives has indicated a possibility for a wide range of application for both material options.  The possibility of utilizing the bio-composite technology in PER to produce higher strength environmentally friendly polymers has not yet been explored but may show great promise.  Where addition of bio fibers to PVC for increased strength seemed futile as the PVC itself was so toxic, PER provides a far more appropriate material to begin researching the benefits of inserting a bio fiber matrix.
The promise of bio-composites and PER as PVC alternatives has indicated a possibility for a wide range of application for both material options.  The possibility of utilizing the bio-composite technology in PER to produce higher strength environmentally friendly polymers has not yet been explored but may show great promise.  Where addition of bio fibers to PVC for increased strength seemed futile as the PVC itself was so toxic, PER provides a far more appropriate material to begin researching the benefits of inserting a bio fiber matrix.<ref name = "biocomp"/>


A complete switch from PVC to PER is not completely feasible currently due to the higher cost of production. There is hope however that while environmental concern increases over the coming years a switch to the more environmentally friendly polymer may provide opportunity for reduction in waste and harmful gas emissions.
A complete switch from PVC to PER is not completely feasible currently due to the higher cost of production. There is hope however that while environmental concern increases over the coming years a switch to the more environmentally friendly polymer may provide opportunity for reduction in waste and harmful gas emissions.

Revision as of 17:07, 17 November 2008

History

Petroleum based W and W have dominated many material processes over the past decade. In recent years the concern with W depletion as well as the environmental impact of such materials has led to an interest in alternative, environmentally-friendly materials. Bio-based polymers have proven to be increasingly popular alternatives in recent years[1].

W(PVC) is a very common thermoplastic polymer utilized in a wide variety of applications such as building materials, pipes and electric wire insulation. Concern has been placed in its wide use as it has a great environmental impact and contains both toxins and carcinogens. In many more flexible PVC products, additives become another concern. In order to make the material flexible, plasticizers are added, most of which are toxic. Phthalates are common additives for this cause, and have been ban in several countries due to their toxicity however complete elimination has proven to be difficult due to the necessity for flexible plastics. Alarm is a particular concern in applications where burning or exposure to sunshine occurs as this often causes harmful gas emissions such as carbon monoxide, carbon dioxide, hydrogen chloride and occasionally phosphene gas[2].

Polymer environmentally-friendly resin (PER) has become a popular alternative to PVC as it is environmentally-friendly, as indicated in the name, and toxin and carcinogen free. Patented in 2003, Polymer Environmentally-Friendly Resin is a fairly new technology is thus not yet widely used. One area of in which PER has become increasingly popular is that of the yoga community and yoga mat production as many yogis are, in general, very environmentally conscious. PER however, has great potential for use in a wide range of applications currently utilizing PVC.

Why PER? Environmental and Health impacts of PVC

Toxins

The most common toxins in PVCs are phthalate W, W and W. Phthalates have been given a large amount of concern as W and DINP, the most common phthalates in PVC, have been listed as probable carcinogens by the W. Studies on animals indicate that the effects of these phthalates may range from gastrointestinal distress to birth defects to various [3].

Lead can be found in large quantities in PVC and during degradation due to heat and sun exposure, it can be released into the air as dust. Lead has a large range of negative health effects but tends to target the W[4].

Finally, dioxin is a by product of the manufacturing process of PVC as well as its combustion. It is a Class I carcinogen according to the U.S. Environmental Protection Agency and may cause reproductive, developmental, hormone or immune system problems[5].

Carcinogens

W, a known carcinogen, is the chemical used to make PVC. Lond term effects have been observed in workers of PVC plants as well as residents surrounding PVC plants. The commonality of interaction with PVC as it comprises many food packages, children’s toys flooring, wallpaper, piping and numerous other applications thus presents concern for extensive interaction with this known carcinogen[6].

Recycling and Biodegradability

PVC’s provide debatably more negative environmental impacts for their worth when recycling. Due to the large quantities of additives in PVC, they can be cycled a limited number of times and must be sorted out of the recycling process in most cases. They also emit harmful gases including W, W and W when melted down and thus extensive harm is caused by their recycling. PVC’s are also completely non biodegradable and therefore their environmental impact is negative weather they are being recycled or not[7].

PER production

The method of producing PER consists of three main steps. Initially a mixture of acetic tri butyl citrate and liquid-phased stabilizer is made. A second mixture of powder-like poly vinyl chloride, filling agent, light stabilizer uvasorb and fireproof agent is prepared, and then the two complete mixtures are combined. Once combined, the mixture becomes a cream-like finished product which is then baked at 170°C and becomes useable polymer environmental-friendly resin[8].

Benefits of PER

The environmental benefits of using PER over PVC are enormous. Where emissions from PVC production are great, PER has little to no harmful emissions even when burned. PER is also biodegradable both in its original form and as combustion byproducts without pollution. Given that there are fewer additives in PER than PVC it is recyclable without risk of degradation of the polymer after repeated recycling. Due to it’s unique composition, recycling PER does not produce the same harmful gases as those produced from recycling PVC.

Given all of these benefits, PER is also successful in fulfilling the desirable qualities of PVC. PER is non-slip, water proof and sun protective just as PVC is[8].These qualities allow PER to be a suitable and environmentally friendly replacement for most PVC products.

Bio-Composites

Increased interest has come from reinforcing bio-material polymers with environmentally friendly fibres.[9] This method has proven to increase strength while maintaining the materials environmental benefits. Natural fibers, such as W [10] and W[11] are embedded in a bio-based polymer which has been proven to increase tensile strength in these materials. Bio- based polymers are often soy-based and show great promise in the environmentally friendly polymer industry. The properties of the bio-based polymers alone do not provide enough strength to be useful in a wide variety of applications. Embedded fibers have increased their usefulness in a large number of applications. A direct link between the cross linking of fibers within the material and material strength has been observed.

Material Efficiency

Recycling

Minimizing material use through more recyclable options may be the best and only option that leads to an environmentally friendly polymer industry. The recyclability of PER is the major contributing factor pushing industry towards its use as opposed to PVC. PVC is unfavorable as a recyclable material and thus is more of less one time use if environmental impact is to be taken into account. Where recycling of PVC does occur, the human labor required to sort it from other plastics is great as many plants do not want PVC and its high additive contents to contaminate the recycled material. Should a switch to PER occur, as a far more recyclable it can be recycled a number of times before additive content it too large for the material to be useful. The option of PERs as a recyclable polymer in replacement of PVC appears to be quite appealing for these reasons. The use of PER as an alternative to PVC has environmental benefits as well as minimizing the need for new materials as recycling will become a viable option again. [12]

End of Life

While PVC incineration may be a more economically viable method of dealing with PVC over switching to environmentally friendly materials, the environmental footprint of this option seems far too large to justify the expense of alternate options. PVCs may be recycled only a limited number of times and when they can no longer be recycled they will remain in landfills as they do not biodegrade. Incineration emits a large number of greenhouse and harmful gasses and leaves a large amount of solid waste such as slag, ash and various types of residues.[12] PERs provide an option for end of life that leave little environmental impact. PER is completely biodegradable.

Suggestions: The future of PER and PER composite materials

The promise of bio-composites and PER as PVC alternatives has indicated a possibility for a wide range of application for both material options. The possibility of utilizing the bio-composite technology in PER to produce higher strength environmentally friendly polymers has not yet been explored but may show great promise. Where addition of bio fibers to PVC for increased strength seemed futile as the PVC itself was so toxic, PER provides a far more appropriate material to begin researching the benefits of inserting a bio fiber matrix.[9]

A complete switch from PVC to PER is not completely feasible currently due to the higher cost of production. There is hope however that while environmental concern increases over the coming years a switch to the more environmentally friendly polymer may provide opportunity for reduction in waste and harmful gas emissions.

References

  1. Jiang Zhu, K. Chandrashekhara, Virgil Flanigan, Shubhender Kapila. “Curing and Mechanical Characterization of Soy-Based Epoxy Resin System” <http://scholarsportal.info.proxy.queensu.ca/pdflinks/08101219511503873.pdf>
  2. SVP Industries. “PVC and Fire” <http://www.svpindustries.com/docs/pvc-and-fire.pdf>
  3. Technology Transfer Network Air Toxics Web Site: Bis(2-ethylhexyl) phthalate (DEHP)<http://www.epa.gov/ttn/atw/hlthef/eth-phth.html>
  4. Agency for Toxic Substances & Disease “ToxFAQs”< http://www.atsdr.cdc.gov/tfacts13.html>
  5. EcoMall. “Health Concerns about plastic toys” <http://www.ecomall.com/greenshopping/ftoys.htm>
  6. Pamela Lundquist, Aisha Ikramuddin. “PVC: The Most Toxic Plastic”. CHEC’s HealtheHouse <http://www.checnet.org/HEALTHEHOUSE/education/articles-detail.asp?Main_ID=185>
  7. Environmental Roadmapping Initiative "Plastics:Impacts, Risks and Regulations"<http://ecm.ncms.org/ERI/new/IRRplastics.htm#issues>
  8. 8.0 8.1 “Method for fabricating polymer environmentally-friendly resin” <http://www.freepatentsonline.com/y2004/0254288.html>
  9. 9.0 9.1 Biocomposites from natural fibres and biodegradable polymers: Processing, properties and future prospects.<http://cat.inist.fr/?aModele=afficheN&cpsidt=14614859>
  10. Takashi Nishino, Koichi Hirao, Masaru Kotera, Katsuhiko Nakamae, Hiroshi Inagaki “Kenaf reinforced bidegradable composite” <http://scholarsportal.info.proxy.queensu.ca/pdflinks/08101219513403958.pdf>
  11. Rowell, Roger M. Biological Systems Engineering Dept., University of Wisconsin.“Potentials for Jute Based Composites”<http://www.fpl.fs.fed.us/documnts/pdf1997/rowel97f.pdf>
  12. 12.0 12.1 PVC waste and recycling. <http://archive.greenpeace.org/toxics/html/content/pvc3.html>

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