Polystyrene Zimm Plot
Convert your scattering data obtained on polystyrene from packaging “peanuts” into a Zimm plot, following the general method in the “HowTo” guide. Do it in Excel, although the HowTo is wrapped around a program called GuiDe (also known as NonZimm). You will need a dn/dc value. One easy way to get it would be to inject your sample into the GPC/MALLS and assume total recovery, then use the integration method (see HowTo on GPC/MALLS)
Other stuff you need: we used HeNe laser light (632.8 nm). The optics were set so that m=1 in the equation regarding how volume should compare from Rayleigh standard (toluene) to the solutions (also toluene). The refractive index of toluene is about 1.495. Other things can be found on the website (http://macro.lsu.edu/HowTo/guide/guide.doc ) especially the appendix and, within that, the section entitled Mechanics of Gathering Data. Once you have Excel make the plot, you may very well find it easiest to just draw the rest graphically.
a) Specify what concentrations you prepared (by weight).
b) Specify your concentrations as g/mL.
c) Specify how you got your dn/dc value.
d) Specify the value you obtained, being sure to include a ± uncertainty term.
e) Specify what angles you measured.
f) Show the I·sin(q) / I(q=90°) vs. q plot.
g) Show your Zimm plot as just bare points.
h) Draw the c = 0 and q = 0 extrapolation lines.
i) Determine Mw, A2 and Rg, if possible. Each one needs a ± estimate.