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25 August 2006 - The website Chem Systems appears to be a good source of information to update the CHEM 381 page.

25 August 2006 - The first phase of the Zimm Plot page is complete. It contains a thorough work through of the example on page 711 of Hiementz.

06 August 2006 - Two files from the original hypertext were transferred over: Head Tail Placement and Tacticity. The Head Tail Placement page provides a a javascript option at the end where a click on an repeat unit "flips" the repeat unit. The intent is to start with a 100% head-to-tail structure, and then put in some "head-to-head" placement, and then show that the number of head-to-head placements is equal to the number of tail-to-tail placements.

30 July 2006 - The Fox Flory Glass Transition Temperature relates the Glass Transition Temperature to molecular weight. A general form of the equation is used to show the effect of molecular weight on a mechanical property. This has been used to introduce the idea of polymer molecular weight.

28 July 2006 - The Mechanical Properties page was upgraded. Previously containing only Young's modulus, two more moduli were added, Bulk Modulus and Shear Modulus.

27 July 2006 - The Fox Equation was added.

26 July 2006 - For the next day or so, the company that hosts my website is migrating everything to a new server. So far the only "loss" I've seen has been that the side links on the Equations page does not function. This indicates that the latest version of the page did not make it through. It's not a cause for panic though--I have the page on my computer and will try to move it through in a day or so.

23 July 2006 - The Mechanical Properties of Polymers page is a list of variables and it includes some equation. It covers Maxwell and Voigt elements. The Voigt is sometimes known as the Kelvin element or the Kelvin-Voigt Element.

9 July 2006 - The Coordinate Transformation javascript converts between Cartesian and spherical coordinates. It has been upgraded to provide both coordinates rounded to the fourth decimal place, and also a table below that shows all the decimals.

4 July 2006 - Work on Vector Derivatives continues. Materials prepared by Bristol that are now listed in Coffee Corner are providing the examples to work off of when putting together ideas in the Math section.

3 July 2006 - Breakthroughs today with making two new Javascripts Series. The Javascript Dot Product allows putting in coordinates for two vectors in 3D real space, and observing both vector length, the dot product, and the angle between the vectors. The Javascript Cross Product calculates the cross product, and shows how for unit vectors, crossing i x j gives k, crossing j x k gives i, and crosing k x i gives j.

2 July 2006 - A big score happened today with finding the del operator, and the discussion on vector calculus. This will be important for understanding more of the math Notation in the more advanced articles about polymer physics. While working on this, it was decided to build Coffee Corner. It has been noticed that several websites have been useful on several occasions for fact checking, and it seemed, if they helped us, they should be helpful to students too. Not wanting to put these all over the website (as had happened in the original Polymer Chemistry Hypertext, it was thought better to collect them all together in one place.

1 July 2006 - Another test was done using Javascript "dice" to build a random polymer on a Z=6 lattice, Dice2 and it gave an average distance very similar to the random walk of a freely jointed chain in 3D space.

30 June 2006 - New content was added to Vectors and work was begun on Linear Algebra. A page was put out on Boltzmann's Distribution, also known as the Maxwell Boltzmann Distribution.


29 June 2006 - Added Poisson's Ratio and Young's Modulus. The Young's modulus page has a matrix on it for the "equation".


27 June 2006 - Added the page about Work of Adhesion and updated the format for Young's Equation. These relate adhesion to contact angle.


24 June 2006 - The work to build the Enthalpy Derivation, was finished.


23 June 2006 - Added the page about Poiseuille's Equation, and prepared separate pages for Specific Viscosity, Intrinsic Viscosity and Relative Viscosity. Also gave the page on Viscosity an update.


22 June 2006 - Finished the page with two 10mers and did the math for the adius of Gyration. A spreadsheet to calculate Rg for a 10mer was added. The spreadsheet calculates radius of gyration for the first example on the Radius of Gyration page. It also calculates the radii of gyration for the two 10mers and for a system named "fiver" (not a polymer) that includes 10 points all located 5 units from the center of mass.


20 June 2006 - Added an animation to Radius of Gyration.


19 June 2006 - The Ideal Chain Javascript page was put up today. It was disappointing to see that the math doesn't quite deliver the expected average End to End Distance of 10, since the polymer chains have a Degree of Polymerization of 100.
    The operation that changed end to end distance to an integer--so it could be put into the distribution--always rounded down (8.9 -> 8 instead of 9) but this didn't seem to account for the entire discrepancy. Further work that calculated the average of the end to end distances (no rounding), showed that values tended to come out a little higher than 9 each time.

    I found a website where the guy said he did a program to simulate dice thrown, and it wasn't perfect. I'll look into it further. Work done on a spreadsheet with the same math formulas also failed to deliver "the perfect 10". After running it 30 times, that average was also "short"--9.08 instead of 10.

18 June 2006 - Some Javascript work has been started. THe first major spin-off from this was the Random Walk Line.


18 June 2006 - The page about Vectors was updated to include the squirrel and the blue jay story.


17 June 2006 - A comment box was placed at the bottom of the home page to make it easier (and faster) for someone to leave feedback.


16 June 2006 - Polymer Segments was finished. It contains two example calculations to show how polymer segments compare to the repeat units of a polymer.


15 June 2006 - Glass Transition Temperature updated.


13 June 2006 - The page about Excluded Volume was updated. The previous picture was replaced, and more information was added.


12 June 2006 - Boltmann's Entropy of Mixing now has a PDF, Boltzmann Entropy Derivation, to show the math between the equation on Boltmann's tomb and Gibb's Free Energy Change of Mixing (Lattice model).