Spectral Sensors by Carl Zeiss

A d d iM e tTMO n -lin e P o ly m e r a n d A d d it iv e s A n a ly s isINTRODUCTION
AddiMet™ is a complete and flexible approach tothe on-line analysis of polymers and additives.
It is modular in design allowing the system to be
optimally configured for the application. UV options
provide the high sensitivity for the measurement oflow level antioxidants e.g. Irganox, Irgafos andBHT (this cannot be done in the NIR). The NIR
option allows the determination of bulk compositionand prediction of physical properties of the polymer
matrix. Several of these options can be costeffectively combined into a single system.

Reference Channel
Carl Zeiss Spectrometer

Optical FiberMCS 551 UV Spectrometer

Optical Probe

THE ANALYSER
The System consist of a Carl Zeiss MCS 500
photodiode array UV/visible spectrophotometer whichis interfaced to the process via optical probes andoptical fibers. A PC running a dedicated software
package written in LabVIEW  controls thespectrophotometer. Charm Works Partial Least
Squares (PLS) tools are embedded in this applicationin order to predict the additive concentrations. The MCS
500 Carl Zeiss modular spectrometer is the heart of
the analyser system. The unique design of thespectrometer ensures reliable measurements in theharshest industrial environments. The analysis is madedirectly in the process stream (melt) using opticalprobes. These operate at up to 10,000 psi (660 bar)and over 250° C and can be installed within a processrheometer or a flow cell. A fiber optic connection
between the probes and the spectrometer enhances
the flexibility of the system.
THE BENEFITS♦ Analysis time greatly reduced♦ Tighter control of blending process is achieved♦ Reduced wastage♦ Customised installation

株式会社

Extruder or Flow Cell
Dicon Multiplexer

Figure 1: On-line analyser

Vankel 7000 with Auto Temp

Hellma Ultra-Mini Probes

Figure 2:

MCS 500 series

スペクトラ・コープ〒164‑0011 東京都中野区中央4‑4‑5第一小林ビル
Tel:03‑5328‑2858 Fax:03‑5328‑2859
URL http://www.spectra.co.jp

Spectral Sensors by Carl Zeiss
THE SYSTEM
ProbesMaximum operating temperature
Operating pressure
Optical fiber
Spectrophotometer
Computer
Digital interface

THE SOFTWAREPolymer Melt Probes mounted in a melt measurementplatform (Rheometric Scientific).
250°Cin excess of 10,000 psi.
600 µm silica core
Carl Zeiss MCS UV seriesat least a Pentium 166 MHz PC with 24 Mbytes ofRAM running Window NT
the computer is equipped with a National Instrumentsinterface card, enabling the performance of thesystem to be monitored by the process control
system and to generate local alarms.

AddiMetTM software controls the spectrometer, analyses
the data and communicates with process control system(all industrial communication protocols supported).
AddiMetTM uses the PLS (Partial Least Squares)
algorithm to predict in real time the concentrations ofantioxidants (simultaneous multicomponent analysis) or
the physical properties of the polymer.
The PLS calibration set is obtained from liquid
chromatographic analysis on samples removed from theextruder. About 30 samples, evenly covering theconcentration range, are required. The exact number ofsamples depends on the number of additives to be analysed
and the quality of the reference analytical data. The model
can be upgraded and optimised by adding new training
samples at anytime.The use of PLS enables simultaneouson-line analysis of multiple additives. Thus further reducing
analysis time.The composition of the polyethylene melt is
inferred in real time rather than waiting several hours for offline chromatographic analysis. The measurement period
is typically 10 seconds. The software on the associated
PC processes the spectra on demand and passes theadditive concentrations to the process control system.

AddiMet™ software is licenced exclusively to Carl Zeissby Process Analysis and Automation LtdCarl Zeiss
Spektralsensorik

D-07740 Jena
Phone:++49 (03641)64 2838
Fax:++49 (03641)64 2485
E-Mail:info.spektralsensorik@zeiss.de
Internet:
http:// www.zeiss.de/spectral