PET polyester fibres are thermoplastic, and lend themselves well to physical modificationc associated with this property. Crimped and textured yarns of all familiar types are available. Production: Polyethylene terephthalate is made by the condensation of terephthalic acid, or a derivative such as dimethyl terephthalate, with ethylene glycol.
These are prepared by dispersing the drug in polymeric base solution. There are some polymers used in preparation of Transdermal patches: Natural polymers: such as, cellulose derivatives, Zein, Gelatin, Shellac, Waxes, Proteins, Gums and their derivatives, Natural rubber, Starch etc. Synthetic Elastomers: e.g. polybutadiene, hydrin rubber, polyisobutylene, silicon rubber, nitrile, acrylonitrile, neoprene, butyl rubber etc. Synthetic Polymers: such as, polyvinyl alcohol, polyvinylchloride, polyethylene, polypropylene, polyacrylate, polyamide, polyurea, polyvinylpyrrolidone, polymethylmethacrylate etc
Retrieved April 17, 2016, from http://www.slideshare.net/ ripestone_ho/polymers-and-their-properties INTERESTING facts about Isotactic Polypropylene Polypropylene is a versatile thermoplastic polymer. It can be moulded into different shapes and sizes and hence, can be put to many uses (material used to make chairs, containers, tools etc.) It is hard but flexible. (semi-rigid) It is lightweight!
Phenols can be used as disinfectants, medical products and etc. Phenols are readily absorbed following inhalation, ingestion or skin contact, and it can be found in human breast milk (Wolff, 2007). It is produce naturally and synthesized as a manufactured chemical. It is an constituent of coal tar, decomposing organic material, human and animal wastes, and as a compound that is commonly found in many non-foods and foods (Xhang, 2008).
Jacques Yves Cousteau writes, “Water and air, the two essential fluids on which all life depends, have become global garbage cans” (Cousteau 1). Recycling is an easy way to take care of our planet. Everyone should recycle because it saves energy and protects animal’s natural habitats. Recycling saves natural energy.
R-DNA technology uses palindromic sequences and leads to the production of sticky and blunt ends. The DNA sequences used in the construction of recombinant DNA molecules can originate from any species. For example, plant DNA may be joined to bacterial DNA, or human DNA may be joined with fungal DNA. In addition, DNA sequences that do not occur anywhere in nature may be created by the chemical synthesis of DNA, and incorporated into recombinant molecules. Using recombinant DNA technology and synthetic DNA, literally any DNA sequence may be created and introduced into any of a very wide range of living organisms.
Heat resistant. Investigating how the composition and the structure affect the parent material of polymers: We are using Plastics widely everywhere and so many types of plastics we have. The additives change the structure and the composition of the polymer.
It 's true that for many of us diapers are not a critical aspect of daily life. Even parents of young children only address dithering needs for a few short years. Interestingly, the impact of the disposable diaper however affects each of us and is a long-lasting trouble. It is currently estimated that 10,000 tons of disposable diapers are tossed into landfills each day. Each of these 10,000 diapers take up to 500 years to decompose, at best.
1.1. Polyesters Polyesters are the polymers that contain ester functional group in their main chain. The polyesters can be classified according to the composition of their main chain as aliphatic and semi-aromatic in addition to aromatic polyesters. Also can be thermoplastic or perhaps thermoses. All common polyesters are thermoplastics (Rosato, L. et al.
In other words, the majority is left to the landfills. And hopefully, it would decompose after being buried for like 5 decades or even more. However, according to the waste statistics from the Hong Kong Environmental Protection Department, the solid waste sent to landfill per day is around 9,000 tons. And with such speed of waste produced, the maximum capacity of the landfills would be eventually
The expenditure for desalination equipment and systems is around $14 billion over the next five years and little R&D is done to improve this technology. The other problem is small profit margins, single digit in most cases, with a lot of competition. Most of the big companies have gone out of the business; DuPont for
According to a new study by Bas W. van Doorn, a political science professor at College of Wooster in Ohio. Doorn studied 474 stories about American poverty from 1992 all the way to 2010. Within the images that were ran alongside these stories, African American people were overrepresented. They appeared in a little more than half images that were portrayed while only making for about 25 percent of Americans below the poverty line.