Colloid Lab

As a general rule, our equipment shall be available for guest groups, especially those scientists that have been granted beam time on the neutron or synchrotron instruments to allow for a complete and proper characterization of their samples. This opportunity is another manifestation of HZB’s mission to offer “neutrons and more” to the users, which includes the support by the scientific and technical staff. Similarly to the regulations for the large scale research instruments, the access to the laser lab is subject to safety instructions prior to access. With these facilities we are near to a complete park of tools for the characterization of colloidal suspensions, micelles, and supramolecular structures generated in aqueous suspension.

The colloid lab hosts equipment for studies to measure physical parameters, complementary to the proposed experiments at the neutron and X-ray user instruments. It also serves HZB scientists in their daily “in-house” research. The lab is run by the colloid physics group within the Institute for Soft Matter and Functional Materials. The available laboratory methods comprise thermally controlled static and dynamic light scattering (SLS/DLS/DDLS). Both are situated in our large class IIIb laser laboratory (LS117) together with a commercial Malvern Zeta-Sizer. Additionally we run three rheometers in a dedicated lab (LS217), one of which is foreseen to be adapted to the small-angle neutron scattering instrument V16. The group research on mesoscopic materials as colloidal suspensions, micelles and supramolecular structures is in this way fully cross-linked with the development of instruments as well as the accessibility to and service of supporting laboratory equipment.

Depending on the state of an accepted proposal, either short term or long term, we offer reduced (DLS, Zeta sizer) or full (+SLS, DDLS) access to our light scattering equipment. The corresponding table shall give an overview about the parameters of our light scattering spectrometers.

As another class of experiments that may be supported by lab experiments we offer for long term proposal users to benefit from our rheology instruments. This shall primarily complement the Rheo-SANS experiments on the VSANS instrument in order to couple structural data to rheological data.

Light scattering instruments

Access to light scattering instruments is subject to the participation to a web based laser security course
Equipment ( user service / limited access )typelight sourcedetector systemsize rangetemperature rangeCuvettes / geometriesn.n.
ALV 4000 DLS / DDLS, SLS He-Ne-laser, 18 mW, 633 nm avalanche photodiode 0.010 - 50 µm 10 - 80°C disposable glass cell, reusable quartz (1 - 2 ml sample volume) Daniel Clemens
Fangfang Chu
ALV 125 static & dynamic light scattering He-Ne-laser, 18 mW, 633 nm photomultiplier 0.050 - 50 µm 10 - 80°C disposable glass cell, reusable quartz cell (1-2 ml sample volume) Daniel Clemens
Fangfang Chu
Malvern Zeta-sizer DLS , Zetapotential frequency doubled DPSS laser, 50 mW, 532 nm avalanche photodiode 0.6 - 6000 nm 2 - 90°C quartz, plastic (10×10 mm²), dip cell for zetapotential measurements

Rheometers

Equipmentrheometer type & supplierfrequency rangetemperature rangegeometries
MCR 702 stress-controlled rotational rheometer MCR 702 (Anton Paar) 10-7 – 102 Hz
  • -20°C - 180°C (convection oven in two motor mode)
  • -40°C - 200°C (Peltier-control in one motor mode)
  • with two motors:
    temperature control with concevtion oven (also suitable with gaseous nitrogen):
    • cone-plate (CP50): R = 25 mm; α=0.991°,sample volume: 0.6 ml
    • plate-plate (PP25): R = 12.5 mm, sample volume (1mm gap): 0.5ml
    • coaxial cylinder (CC20): gap width: 1 mm, sample volume: 7 ml
  • with one motor:
    • temperature control with Peltier heating: all geometries as for the MCR 301 except the Rheo-SANS
    • temperature control with concevtion oven (also suitable with gaseous nitrogen): all geometries as listed for two motors
MCR 301 stress-controlled rotational rheometer MCR 301 (Anton Paar) 10-5 – 102 Hz -40 – 200°C ± 0.01°C (Peltier-control)
    various geometries are available:
  • cone-plate (CP50): R = 25 mm; α=0.991°,sample volume: 0.6 ml
  • plate-plate (PP25): R = 12.5 mm, sample volume for 1mm gap: 0.5 ml
  • coaxial cylinder (CC27) :gap width: 1.128 mm, sample volume:
  • coaxial double gap (DG26.7): gap width: 0.42 mm and 0.46 mm; sample volume: 3.8 ml; for low-viscosity samples (0.4 mPas < η < 200 mPas)
PAV squeeze flow rheometer (IdM Ulm) 10 – 5000 Hz 5 – 60°C ± 0.02°C various gap heights for different viscosity ranges
  • gap heights: 10 μm up to 200 μm
  • sample volume: 100 μl
TR torsional resonator (IdM Ulm) eigenfrequencies at f = 13, 25 and 77 kHz 5 – 60°C ± 0.02°C
  • cylinder: f = 25 kHz and 77 kHz, sample volume: 7 ml
  • dumbbell: f = 13 kHz, sample volume: 11 ml