LALLS low-angle laser light

The correction of absorption depends on the geometry of the cell and the scattering volume. Different relationships have been proposed to correct the Rayleigh factor measured with conventional goniometers, in which the detector rotates around the sample m a horizontal plane (Brice et al. 1953, Forss et al. 1967, Pla et al. 1977). With LALLS (low angle laser light scattering) pho-... 

LALLS = low angle laser light scattering MALLS = multi-angle laser light scattering LS = either LALLS or MALLS MWD = molecular weight distribution IV = intrinsic viscosity [ ]... 

Lab-on-a-chip analyzers, 941 Laboratory electronic, 127-130 operations, in microfluidics, 940 paperless, 127 recorders, 52 -53 LabVIEW, 99,102-103, 745 LALLS (low-angle laser light scattering), 951-955 Laminar-flow burners, 233 LAN (local area network), 105,107 LAPS (light-addressable... 

LALLS low-angle laser light scattering (detector)... 

A number of the limitations of conventional SEC can be overcome through use of a low angle laser light scattering (LALLS) detector attached in series with a concentration... 

The observations and questions raised by these workers helped stimulate the experiments which are presented here. In this work, size exclusion chromatography with low angle laser light scattering detection (SEC/LALLS) was used to probe the distribution of branching functionality in multiarm macromolecules of styrene/isoprene and styrene/buta-... 

SEC System, Data Processing, and Chromatography Procedures. The SEC/LALLS system contained a Model IlOA pump (Altex), Model 7125 injector (Rheodyne), KMX-6 Low-Angle Laser Light Scattering Photometer (LDC/Milton Roy), and a Model 98.00... 

The concentration of the polymer molecules eluting from SEC columns is continuously monitored by a detector. The most widely used detector in SEC is the differential reftactometer (DRI), which measures the difference in refractive index between solvent and solute. Other detectors commonly used for SEC are functional group detectors ultraviolet (UV) and infrared (IR), and absolute molecular weight detectors low angle laser light scattering (LALLS) and in-line continuous viscometers. Applications of these detectors to SEC analysis will be discussed later in the Multiple Detectors Section. Other detectors also being used are the densimeter (11-19) and the mass detector (20-23). 

Size exclusion chromatography has been greatly enriched recently by the advent of two commercial detectors, the real-time differential viscometer (DV) and the low angle laser light scattering (LALLS) photometer. The only DV detector currently available is offered by Viscotek in Porter, TX, as the model 100. 

This paper deals with a detailed analysis concerning the determination of M , Mw and MWD of lignins using respectively VPO, low angle laser light scattering (LALLS) and SEC. In addition, recent results obtained by on-line LALLS-SEC are presented. 

Low Angle Laser Light Scattering (LALLS) results indicate, that at lower DVB/RLi molar ratios, a relatively narrow molecular weight distribution (1.04-1.1) of star-branched polymers can be synthesized. In contrast, DVB/RLi ratios greater than 11 can lead to rather broad molecular weight distributions (Mw/Mn = 1.3). 

---