KULIM Hi-Tech Sdn Bhd

Association and solubility studies of mixed polyglycol ether surfactants in water

Bassem M. Bajouk, Rolf O. Sköld

Department of Applied Surface Chemistry, Chalmers University of Technology, Kemivägen 10, SE-412 96 Göteborg,Sweden

The effect of varying the molecular structure and the type of counter ion of polyglycol ether based anionic

surfaceactive components on the processes of phase separation, adsorption to the air-water interface and

molecular association in aqueous model metalworking formulations containing a polypropylene glycol was

studied. Phase separation and micellization were studied via static surface tension measurements and by

using an instrument, which enables the automatic scanning of temperature and concentration dependent pH,

turbidity and conductivity data. The anionic surfactants investigated were highly water-soluble and the

surface tension isotherms of all formulations were found to display a common anomalous trend characterized

by an initial maximum in the Gibbs surface excess function followed by a plateau region before a second

maximum occurs just before the concentration taken to indicate micellization. The aqueous mixtures in most

cases displayed concurrent phase separation and micelle formation, which has to be taken into account when

comparing critical micelle concentrations (CMCs). The present availability of parallel data, turbidity data in

particular, allowed incipient phase separation to be detected. This is a circumstance, which would otherwise

pass unnoticed, since it is not visually detectable. Results are considered industrially useful since the control

of the isotropic temperature - concentration space is a key aspect in the design and fine-tuning of

environmentally benevolent aqueous functional fluids for specific applications.

© 2002 Elsevier Science B.V. All rights reserved.

Colloids and Surfaces A: Physicochem. Eng. Aspects 212 (2003) 65 -/77

SPR Navi™ 220A - THE AUTOMATED MP-SPR

SPR Navi™ 220A is the top of our line. Choose SPR Navi™ 220A, if you want to perform high-throughput MP-SPR with minimum dead-volumes and increased measurement confidence. As shown in the comparison, it is fully automated. Also here, to fully enjoy the MP-SPR, we recommend the additional set of lasers.

Key Features of SPR Navi™ 220A:

True Goniometric SPR

Unlike most SPR systems, SPR Navi™ 220A is a true goniometric SPR. This eanbles a wide angular scan range ( = 40–78°) that produces a complete SPR curve with absolute angle information. The true goniometric SPR configuration confers great advantages as it widens the range of refractive indexes at which you can measure, allowing you to characterize surfaces in gas and/or liquid. It also allows you to check the quality of user-defined surfaces before sample injection, providing you with additional evidences. In other words, the wide angular scan range makes SPR Navi 200 an extremely sensitive and versatile characterization instrument.

Customizable flow cell

SPR Navi™ 220A comes with dual measurement channels for in-line referencing or duplicate measurements. In addition, the easily accessible flow-cell can be customized for user-specific experiments, thus broadening your experimental capabilities. For instance, BioNavis can provide electrochemical flow cells or flow cells equipped with optical fibers for surface illumination. The flow cell shape can also be customized to tailor the flow dynamics to your needs.

Flexible sensor-slide system

With the SPR Navi™ 220A instrument, you can use the innovative sensor-slide holder for easy “drop-in” placement of your sensor-slide into the instrument. It allows users to change surfaces within seconds, making SPR Navi™ 220A an extremely convenient instrument to work with. The sensor-slide holders can be labeled and used for long-term storage of your custom-modified surfaces. Sensor-slides can be modified outside the instrument, with a great number and combination of layers, prior to the actual analysis. This unique removable sensor system provides additional flexibility. It allows you to combine SPR data with other widely used techniques to provide supporting information, including surface topography, surface wettability, chemical composition, photochemical processes, swelling, adsorption...

Contamination free MP-SPR

The proprietary optical elastomer in the SPR Navi™ 220A finally does away with the need for messy and potentially contaminating index-matching oil. The result is a contamination-free environment for your measurements. The optional immobilizer, a horizontally oriented stand-alone flow cell, can be used for in-situ functionalization of SPR slides. This further minimizes the risk of cross-contamination and enables minimal sample depositions.

Contact Angle.

DEMO.

KHT did a Demo in one of our Top Universities.

Theta with KSV software. We got 3hrs to prove.

Surface Plasmon Resonance SPR BioNavis 200

Dip Coating, LB and LS methods have been shown to be excellentmethods for controlled preparation of thin films graphene and graphene oxide. The methods offer great amount of control for depositing dispersed SG and SGO produced by the liquid exfolia-tion methods. As the liquid exfoliation methods are recognized as some of the most potential methods for producing graphene in industrial scale, these deposition methods are of great impor-tance in graphene research.We introduced more thoroughly two powerful optical methods for characterizing graphene films before and after deposition, PM-IRRAS and SPR. With the KSV PMI 550 it was possible to record detailed IR spectra of floating and deposited layers to determine the chemical composition. The SPR Navi 200 was capable of characterizing the thicknesses and the complex refractive indices of the deposited layers. It was possible to distinguish single sheet and aggregated graphene from each other.

Potentiostat ACM

The potentiostatic test is usually performed to determine resistance to pit initiation at a given potential and to simulate galvanic situations using any of Gill AC 8 12 Field Machine and manual potentiostat set to a stable potential whilst recording the current. In the study of pitting the cyclic sweep method can have problems related to sweep rate and too much pitting propagation before sweep reversal. The use of individual samples held at potentials around the suspected pitting potential will allow the correct determination of the pitting potential. For example the graph below shows current versus time for samples polarised at different potentials.

Corrosion Testing and Study

Cortest was formed in 1977, and since then, Cortest has grown to include a family of related companies providing corrosion testing equipment, corrosion testing services, technical consulting, field service, and training courses.

Cortest Incorporated specializes in a systems approach to meet all of your corrosion testing needs. We manufacture a comprehensive line of corrosion testing apparatus and support equipment that combine to form complete testing capabilities for both static and dynamic test conditions. It is this ability to ensure equipment compatibility and proven system performance which makes Cortest a unique single source of supply for your test equipment needs.

For the past 25 years, Cortest has manufactured laboratory corrosion testing equipment, as listed below. Please select your areas of interest for additional information.

Proof Rings and accessories, for testing of stress corrosion cracking in accordance with NACE Test Standard TM-01-77-90. The Cortest Proof Rings provide an economical but effective way to accurately determine the Stress Corrosion Cracking (SCC) susceptibility of metals in different environments.

Autoclaves for high temperature and high pressure tests at 5,000 psi (350 bars) and 600°F (315°C) (up to 20,000 psi (1400 bars) and 1100°F (600°C) for specific systems).

Slow Strain Rate Test (SSRT) systems with the CERT machines for Constant Extension Rate Tests from 10^-5 to 10^-8 in/sec, including a variety of environmental chambers and controls, and featuring the new CVI (Computer Virtual Instrument).

Corrosion Fatigue Test system extending the capabilities of the CERT machine and simulating a wide range of loading cycles.

Recirculating Test Loop to refresh autoclave systems.

Multiphase Test Loop for studying behavior of materials under multiphase flow conditions.

Training Courses on corrosion, metallurgy, and multiphase flow.

Instrumentation/Sensor Design. Customized instrumentation and sensors for corrosion load, steam, pH, O₂, H₂ and other measurements.

Corrosion Measurement in laboratory equipment.

Custom Equipment for specialized applications. Aside the large range of laboratory equipment available, Cortest has a long experience in customized laboratory equipment. The combination of electrochemical and mechanical testing has been meeting the individual needs of corrosion engineers for all kind of corrosion testing requirements.

Advertisement of SPR Navi 200

The stand-up poster of Bio Navis product which is SPR Navi 200 is being displayed at one of our Malaysian top universities' souvenir shop to attract potential lecturers or students.