B+-+Synthetic+Fibres

Joanna Chan, SCH4U1 Presentation Date: November 3rd, 2010 ** Seminar Unit Topic: Structures and Properties  ** ** What impact has the development of synthetic fibres, such as nylon, had on society? ** ** CHEMISTRY of Synthetic fibres **

- Man-made textile fibre produced entirely from ** chemical substances **, unlike those man-made fibres derived from such natural substances as cellulose or protein. (Source: Britannica Encyclopedia) 3 main types of synthetic fibers: regenerated, true synthetic, and mineral ** Regenerated:  ** cellulose fiber (from the walls of plant cells), taking bits of natural materials (wood, cotton) & rearranging them (Rayon, Acetate) ** True Synthetic:  ** Nylon, Polyester, Acrylic, Olefin, Spandex ** Mineral:  ** Glass fibres and metallic fibres - Comes in many different forms, made from many types of materials - Useful in its variety of applications such as in disposable diapers, car seats, the carpets in seat fabrics (for durability), in plastics (to help strengthen), seat beats, filtration (auto, liquid, home, furnace), in air filters to trap particles, mattress covers, but most notably in ** Textiles/Clothing ** **__ How True Synthetic Fibres are Made __**

** -  ** arranging polymers of various chemical composition into various chemical structures for the desired properties ** Polymer ** : any type of molecule constructed by repeatedly connected by a single base unit, the monomer, side-by-side to form a long chain of molecules. ** Monomers ** : can vary in molecular composition and structure, different atoms or carbon rings can be present, many ** organic compounds ** can polymerise as well. - Polymers are not the only basic component in creating synthetic fibres: compounds such as silicon dioxide (glass) can be made into Fiber glass ** In a mixture of ** ** Single Polymer Chains  ** ** -  ** Not much order, arranged very randomly and weak - They intertwine, overlap and twist in 3D dimensions - It takes very little energy to separate the molecules since the attraction binding the separate molecules is weak In order to create the strength and durability that synthetic fibres have, the mixture of single polymer chains are:



- Melted into its liquid state - Forced and pushed though microscopic holes of a submerged spinnerette (a shower head/strainer-like structure) - Molecules harden into fibres - Pulled/stretched to orient them as they pass through the spinnerette, to strengthen it    - Cooled and becomes stuck in its existing formation of a single fibre ** Single Fibre  ** - Strong structure - Takes a great deal of energy to extract a single molecule from the structure - Ability to be enhanced though arranging a countless number of them into complex structures ** __ Properties __ ** ** The organized structure of synthetic fibres is a reason for their desirable properties. The properties of synthetic fibres are dependent on 2 factors: the chemical composition of the polymer and the arrangement of multiple fibres ** ** 2 types of arrangements: Woven and non-woven  ** Non-woven synthetic fibres separate freely, making them great insulators Woven synthetic fibres, less malleable structure, remain in position, used well in textiles Impact on Society…Advantages and disadvantages ** Advantages: TEXTILES! **  - One of the first synthetic fibres to be introduced was Nylon (solution spun polymer) - Breakthrough in the textile industry ** (“industry’s biggest money maker”) ** - Nylon was first manufactured in U.S 1939 as a replacement for silk, most popular for the making of women’s stockings - Among other synthetic fibres and opposed to natural fibres (cotton, silk, wool), Nylon is still commonly favoured for its flexibility, high strength, “wear” properties, abrasion resistance, stands up to water (ability to absorb very little) - It is versatile, mass producible, light weight, lasts long and recovers well from wrinkling and creasing - According to industry analysts, man-made fibres, including cellulosics and synthetics accounted for 58% of all fibre demand in 2006 ** Disadvantages: ENVIROMENTAL IMPACT! **  - Synthetic fibres are produced through petrochemicals ** __ Production of petrochemicals: __ ** Dependent on declining oil and gas reserves through fossil fuel resources (non-renewable); high greenhouse gas emissions, harmful to us and the environment; energy-intensive, fibres are not biodegradable, hard to recycle

** Sources (APA format): ** // polymer: wet-spinning of polymeric fibres //. [Art]. Retrieved  October 31, 2010 , from Encyclopædia Britannica Online: http://www.britannica.com/EBchecked/topic-art/468696/276/Stages-in-the-wet-spinning-of-polymeric-fibres Adshead, J. (2010). Synthetic Fibers. // Grolier Multimedia Encyclopedia. // Retrieved  November 1, 2010  , from Grolier Online http://gme.grolier.com/article?assetid=0282400-0 Krasny, J. F. (2010). Nylon and Other Synthetic Fibers. // The New Book of Knowledge. // Retrieved  November 1, 2010  , from Grolier Online http://nbk.grolier.com//cgi-bin/article?assetid=a2021390-h Burke, M. (2008, March) Green couture. Chemistry World, Vol 5, No 3, 58-61. Retrieved November 1, 2010, from http://www.rsc.org/images/Synthetic%20fabrics_tcm18-114532.pdf Chemistry of Synthetic Fibers,  Eagan   High School   Honors Chemistry. (2008) [Online Video, iTunes Podcast]. Retrieved October 31, 2010, from http://www.eagan.k12.mn.us/fletcher/acn/projects.xml