PET water

Polyesters, The healthiest trend coming out of the plastics industry— personal health, that is—is the ubiquitous PET water bottle. Medical doctors all agree that the increased daily consumption of water enhances well-being. The improvement in producing PET, polyethylene terephthalate, in the 1970s, led to this pervasive replacement of glass bottles because of the cost and portability. 

The corrosion film on Cor-Ten A contains between 30 and 70 wt pet FeOOH, about 4-12 wt pet loosely-bound water, about 1-5 wt pet water of hydration, and the balance hydrated Fe203. No significant concentrations of FeO, Fe203, Fe30i, FeSO, and Fe(0H)2 are present. The corrosion film on carbon steel is similar to that on Cor-Ten A in short exposures. 

On the other hand, there are also studies showing the effects of UV irradiation on the change of migration characteristics of the matrix polymer, (i.e., effect on the migration of phthalate ester plasticisers from clear PET water bottles [87]), and some data are provided on the effects of ionising irradiation on polymer additives, monomers and polymers themselves in general [88]. 

Polyamide (PA) fibres have high strength and tenacity, excellent abrasion resistance and higher elongation than PET. Water absorption of PA 6 and PA 6.6 is relatively high (up to 6%), while that of PA 12 is only 0.3%. Together with UV radiation, the absorbed water may split the relatively weak peptide bonds of polyamide, so it is of little use in outdoor applications. 

Two reaction vessels were prepared one containing 100 mL of seawater and approximately 5 g of 1 cm sterilised pieces of PET water bottles, the second with twice the volume of seawater and number of PET tokens. Further details are published elsewhere [39]. Individual PET pieces were sampled from the flasks at the end of nine months. Samples were cleaned by sonication in 70% ethanol for one hour. XPS analysis was then performed, both on the modified samples taken from reaction vessels and on reference PET samples not exposed to bacterial interactions, to detect modifications to the polymer surface made by the bacteria. XPS analysis was performed with the same parameters as described in section 2.1... 

E.7.5 Calculate an LCA for an aluminum reusable water bottle and compare the results to the LCA for PLA and PET water bottles. How many times would you have to reuse an aluminum water bottle to equal the GHG emission and waste generation of PET plastic water bottles. 

The polymers discussed to this point are reasonably linear. They can be remelted or redissolved and are members of the general class of thermoplastic polymers. For example, a used PET water bottle can be chopped into flakes and then remelted and fabricated into another article such as a flower pot, golf tees, or many other items. These thermoplastics are predominantly linear. Even in the case of polyethylene, where there is often some branching, they soften when heated and can be reshaped or molded into new articles. However, if the polymer is not linear but three dimensional it cannot be reshaped. These polymers are formed in the mold and take a set. After the polymerization is complete, they cannot be remelted and reshaped. These are called thermoset polymers or thermoset resins. 

The final category of end markets is for injection moulding/other outlets. These applications account for less than 20,000 tormes/year of rPET at present and are very varied. rPET can be filled with glass fibre, for instance, and injection moulded to form complex engineering components. It is also injection moulded to form the barrel of the Pilot B2P (Bottle2Pen) Figure 5.2. This clear cylinder is designed to look like a PET water bottle, complete with a label panel, and is a quality pen with the body made from 100% rPET. 

Which of following liquids will completely wet PET water (71.99), benzonitrile (35.79), pyrida-zine (49.51), glycerol (63.4), adiponitrile (45.5) and acetone (23.3) Explain briefly your answer. The numbers in parenthesis arc the surface tensions in mN m at 20 °C. 

Carbonation appears to affect antimony migration from PET water bottles. Several researchers have reported higher levels of antimony migration in carbonated compared to non-carbonated mineral water (Keresztes et al. 2009) or to ultra pure water, especially at higher storage temperatures (60 °C) (Bach et al. 2013). 

This is going to supply the cold water that courses through the condenser whether that condenser is set up for reflux or is part of a distillation configuration. The pump need not be very strong. In fact, the perfect example is one of those little, submergible fish tank pumps that one can find at any pet store for about 10. All the chemist does is attach a hose to the outlet, chunks the little pump into a bucket of ice water, attaches the hose to the condenser and there it is. An alternative source is that little pump that s attached to the windshield washing fluid reservoir of any car in a junk yard. The chemist removes the reservoir (pump still attached), applies an adapted power source to the pump and uses the plastic reservoir to hold the ice water. 

During the rinse cycle, polyethylene particles float to the surface of the water bath. The higher density PET and PVC particles sink to the bottom of... 

Results obtained for two mixed plastics are summarized in Table 4. A balance exists between process temperature, plastics feed rate, and product yields (67). For example, lower temperatures increase wax formation due to incomplete depolymerization. Slower feed rates and increased residence times reduce wax formation and increase the yield of Hquids. The data summarized in Table 4 illustrate that the addition of PET to a HDPE PP PS mixture changes the performance of the Conrad process. Compared to the reference HDPE PP PS mixture, increased amounts of soHds ate formed. These are 95% terephthahc acid and 5% mono- and bis-hydroxyethyl esters. At higher temperatures, apparentiy enough water remains to promote decarboxylation. 

Pet foods are produced in canned, semimoist, and dry forms. Canned pet foods contain approximately 78 to 82% water and have a strong appeal to both pets and owners. Semimoist foods have moisture contents of 25 to 50%. Dry-type foods contain 10 to 12% moisture and supply about 90% of the nutrition consumed by dogs and 72% of the nutrition eaten by cats. 

Dry Foods. Dry foods are concentrated sources of nutrition and provide the most economical nutritional value because water in canned foods is expensive. Dry foods tend to scrape the teeth as pets eat, minimizing tartar deposition. When dry food is moistened prior to being consumed, tartar accumulates in a manner comparable to deposits observed with caimed foods. Approximately 95 to 98% of dry-type cat and dog foods are made by the extmsion process the remainder is made by pelleting or baking. 

Chemical Properties. The hydrolysis of PET is acid- or base-catalyzed and is highly temperature dependent and relatively rapid at polymer melt temperatures. Treatment for several weeks in 70°C water results in no significant fiber strength loss. However, at 100°C, approximately 20% of the PET tenacity is lost in one week and about 60% is lost in three weeks (47). In general, the hydrolysis and chemical resistance of copolyester materials is less than that for PET and depends on both the type and amount of comonomer. 

When PET is extracted with water no detectable quantities of ethylene glycol or terephthaUc acid can be found, even at elevated extraction temperatures (110). Extractable materials are generally short-chained polyesters and aldehydes (110). Aldehydes occur naturally iu foods such as fmits and are produced metabohcaHy iu the body. Animal feeding studies with extractable materials show no adverse health effects. 

Toxicity. Sodium fluoroacetate is one of the most effective all-purpose rodenticides known (18). It is highly toxic to all species of rats tested and can be used either in water solution or in bait preparations. Its absence of objectionable taste and odor and its delayed effects lead to its excellent acceptance by rodents. It is nonvolatile, chemically stable, and not toxic or irritating to the unbroken skin of workers. Rats do not appear to develop any significant tolerance to this compound from nonlethal doses. However, it is extremely dangerous to humans, to common household pets, and to farm animals, and should only be used by experienced personnel. The rodent carcasses should be collected and destroyed since they remain poisonous for a long period of time to any animal that eats them. 

Fluoroacetamide. Fluoroacetamide [640-19-7], FCH2CONH2, is a white water-soluble soHd having mp 108°C (14). It has been used as a rodenticide and has been reported to have a better acceptability to rats than sodium fluoroacetate (29). However, like the latter compound, its misuse has caused deaths to farm animals and pets (20). 

Polyester. Poly(ethylene terephthalate) [25038-59-9] (PET) polyester film has intermediate gas- and water- vapor barrier properties, very high tensile and impact strengths, and high temperature resistance (see Polyesters, thermoplastic). AppHcations include use as an outer web in laminations to protect aluminum foil. It is coated with PVDC to function as the flat or sealing web for vacuum/gas flush packaged processed meat, cheese, or fresh pasta. 

Ethylene glycol esterification of BHET is driven to completion by heating and removal of the water formed. PET is also formed using the same chemistry starting with dimethyl terephthalate [120-61-6] and ethylene glycol to form BHET also using an antimony oxide catalyst. 

Propylene glycol is also an effective humectant, preservative, and stabilizer and is found in such diverse apphcations as semimoist pet food, bakery goods, food flavorings, salad dressings, and shave creams. Humectancy, or the capabiUty of retaining moisture in a product, is a result of the vapor—Hquid equihbria of the glycol—water system and can be estimated from tables provided by suppHers (27). 

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