Friday, April 15, 2011

Intrinsic Viscosity

Solution Intrinsic Viscosity

Sample Type Required Quantity Equipment Used
1 Rheotek Viscometer


This procedure is used to determine the intrinsic viscosity (IV) of the material. IV is a measure of the Molecular Weight (MW) of PET. The properties of PET are better at higher MW (higher IV) and worse at lower MW (lower IV). Comparing the SIV results from resin and molded parts can provide an understanding of the drying and process conditions.


The test procedure used is ASTM D4603. The solvent system used is 60% phenol/ 40% tetrachloroethane. The PET concentration is 0.50% and samples are analyzed at 30°C. The test can be run on resin, film, preforms and bottles. Corrections are made for samples if they contain >1.% additives or colorants. It is important to know the level of additives present when submitting a sample for analysis. PTI uses Rheotek equipment to measure IV . SIV data reported to the customer will be measured at a single concentration to obtain the inherent viscosity. The intrinsic viscosity is mathematically calculated from the inherent viscosity using the Billmeyer Equation.

Friday, March 11, 2011

Intrinsic Viscosity

Intrinsic Viscosity

It defeats the purpose of participating in the recycling and the use of green products, huge amounts of fresh water, and dwindling natural resources. But you have to wash the recycled plastic. Treatment plants to use up to 100000 gallons of water a day, mainly for the expulsion of other food containers and chemicals before it can be shredded into chips for use in plastic and returned hundreds of industrial applications.

Now add to this the fact that we were thrown some 40000000000 plastic bottles in landfills this year. Why so many? Well, the dollar is, of course, are expensive to recycle, and not return a lot of profit.

Ride to the rescue ECO2 Plastics, based in San Francisco, California. ECO2 does not throw anything in vain - water or chemicals. Our company is established for the first time in the water recycling by the FDA, a process, known as ecosystem ECO2. Process employed, biodegradable corn-based carbon dioxide solvent and liquid (captured from power plants, and interest added), and a bathroom in a closed system which cleans and dissolves buildup and distilled, and then to remove sugars and glues, and isolated until it can be reused.

And savings of billions of gallons of water per year, not to mention the landfill. Patented process developed by the research partnership with Honeywell FM & T and the United States of America, Department of Energy (DOE).

unrecycledWaterBottles2005_845BPS_largeThe recycled plastics from this process is the highest level of quality. It's free and odor pollution to 100 ppm. Each test is £ 1000 on material viscosity, melt flow, density and moisture content of plastic. The content of the ideal product.

Water and waste does not deserve any additional costs. ECO2 process allows the production of the highest level of product quality with the least possible cost - financial or environmental. With this system, plants can reduce costs by 3 / 1 for the effect to filter their water bill. Factory first started using the process of water conservation in October 2008, on the bank of the river, California, which is currently in the process of development and transfer to a new location in Northern California.

ECO2 product is almost identical to traditional plastic recycling, but the production is more efficient and earth friendly. Plants that use this process can be a significant increase in the number of plastic bottles recycled in the United States and Europe each year, and there is no logical reason to recycle any other means.

Not only today's technology PopSci 0940 from 2-045 1ECO2's pet (polyethylene terephthalate), recycled. United States Council (USCAR) Vehicle Recycling Car Research Partnership (VRP), (which consists of researchers from Daimler Chrysler, Ford and General Motors), has a contract with the ECO2 technology assessment for recycling. ECO2 because the evolution of the processes that will sue density (high density polyethylene), polypropylene, automotive parts unrecyclable previously, plastic and others. Since this technology removes the fear of plastic materials recovered "shredder residue" - (Article stayed at the "torn apart" the end of vehicle life (ELV), household appliances and other materials significant large projects, grinding hammer, or grinder) - is part of the process of re- recycled.

Called ECO2 process - eco.logical.recycling - because it eliminates the use of water, respects and preserves the environment, while delivering high-quality recycled plastic flake, which was approved by the FDA for use in contact with food. Really, the Earth-friendly products at no extra charge, if not lower costs.

Make plastic recycling more ecological and economic more than that, and simply make more sense - yes, it eco.logical.recycling!

Negative Intrinsic Viscosity and Positive Intrinsic Viscosity

Negative Intrinsic Viscosity and Positive Intrinsic Viscosity

A new response to old posts raised a good question: can the intrinsic viscosity is negative?

Oddly enough it can be. I'm not in that area, but there are 17 hits on Google Scholar "negative intrinsic viscosity" and many were published in journals is good, so it looks real. Or, as my opinion, the reproducible data. But as usual in science, the challenge is to interpret the results.

I have not even read all the articles, so this is my big chance to introduce my foot in my mouth. I will begin collecting the reference and will post what I have learned, so public humiliation is a real possibility here.

My guess is that the kind of the polymer chain in poor solvent (hydrogen bonds, the interaction of the poles ...) break until the solvent has a lower concentration, leading to a negative intrinsic viscosity - and the need for a new theory explain. Yes, go with a new theory of the old theory of a certain set of assumptions that are no longer valid.

That said, I'm now wondering about the possibility of this effect occurs in reverse order, but do not realize. ie, polymer hydrogen bond strength is more or what do you think will result in a solvent with a higher visocosity, but because the viscosity of the polymer leads to a higher resolution, this "extra" is not seen because it is easy to Just to explain to the viscosity of the polymer strict increase. How can you determine this?

First step: for literature. As so often said, six months in the lab will save you an afternoon in the library.