Molecular Weight Analysis
The molecular weight and molecular weight distribution of polymers are one of the most basic data for studying the properties of polymers and polymer materials. It involves the mechanical properties of polymer materials and their products, the rheological properties of polymers, the selection of polymer processing properties and processing conditions. It is one of the basic data required for the study of specific polymerization reactions and the structure of specific polymers in the fields of polymer chemistry and polymer physics. In addition, molecular weight is also an important characteristic of biological samples such as proteins and polysaccharides.
As a professional reliability third-party testing organization, T,C&A Lab can provide Molecular Weight Analysis service according related standards and industry requirements. Welcome to contact our experts for consultation.
Our analytical range
According to different materials, different systems of testing methods are selected to do molecular weight testing, including plastics, rubber, and other related polymer materials, especially the molecular weight detection of ultra-high molecular weight polyethylene. The detection system should be aqueous phase system, tetrahydrofuran (THF) system, (DMF system) and so on.
Polymer molecular weight testing techniques
- Gel Permeation Chromatography (GPC)
- MALDI TOF-MS
- Number-average molecular weight
- Determination of weight average molecular weight by light scattering
- Viscosity method to determine relative molecular weight of polymers
Gel permeation chromatography (GPC) is based on the separation mechanism of size exclusion. It is used to separate substances with smaller relative molecular mass through a stationary phase with molecular screening properties, and it can also analyze polymer homologues with different molecular volumes and the same chemical properties. It has been widely used in the measurement of molecular weight and molecular weight distribution of polymers.
Gel chromatography can not only be used to separate and determine the relative molecular mass and relative molecular mass distribution of polymers, but also can separate fat-soluble and water-soluble substances according to the different gel fillers used. The separation relative molecular mass ranges from several million to less than 100.
The determination of polymers by matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI TOF-MS) can be used to obtain the average molecular weight and polymerization dispersion data of polymers sensitively and quickly. The absolute molecular weight, segment mass and end group mass of each polymer chain can also be obtained from high-resolution MALDI TOF-MS spectra.
Polymers are composed of homologous mixtures with the same chemical composition but varying degrees of polymerization, that is, a mixture of polymers with different molecular chain lengths. The average molecular weight is usually used to characterize the size of the molecule.
When a beam of light passes through the cylindrical sample tube, most of the light continues to travel after being transmitted, while other directions also emit scattered light due to the refractive index of the medium in the solution. Since the refractive index of the medium depends on the dielectric constant of the medium, which is the result of the density and concentration of the medium, the relationship between the dispersion of the solution and the molecular weight of the polymer can be known according to the Van-Hoff equation and the Willy expansion.
Viscosity method: Since there is a certain relationship between the viscosity of a polymer solution and the molecular weight of the polymer, the viscosity is used to determine the molecular weight of the polymer. The molecular weight measured by the viscosity method is the viscosity average molecular weight.
Standards we test to
ASTM D5296, ASTM D6579, ASTM D6474, ASTM D4001, ASTM F2214, ASTM F2003, ASTM F2759, ASTM D2503, ASTM F2565, ASTM F2381
In addition, the experts in our Molecular Weight Analysis Laboratory also provide a variety of custom services as your needs and requirements. Let's discuss the custom services with our experts for free.
Instruments and data
T,C&A Lab's services include, but are not limited to
Note: this service is for Research Use Only and Not intended for clinical use.
- Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES)
- X-Ray Fluorescence (XRF) Testing
- X-Ray Photoelectron Spectroscopy (XPS) Testing
- Infrared Spectroscopy Testing
- Ultraviolet Spectrum (UV) Testing
- Mass Spectrometry Testing
- Micro-Raman Spectroscopy Testing
- Nuclear Magnetic Resonance Spectroscopy Testing
- Elemental Analysis
- Structural Characterization
- Morphology & Size Analysis
- Corrosion Inhibitor Testing
- Crevice Corrosion Testing
- Electrochemical Corrosion Testing
- Galvanic Corrosion Testing
- High Pressure High Temperature (HPHT) Corrosion Testing
- Hydrogen Embrittlement Testing
- Intergranular Corrosion (IGC) Testing
- Pitting Corrosion Testing
- Salt Spray Testing
- Sour Service Corrosion Testing
- Stress Corrosion Cracking (SCC) Testing
- Sulfide Stress Cracking (SSC) Testing
- Thermal Analysis
- Mechanical Testing
- Non-Destructive Testing
- Performance Testing
- Pharmaceutical Testing
- Chemical Analysis
- Case Depth Testing and Analysis
- Grain Size Analysis
- Particle Size Distribution Analysis and Testing
- Coating Thickness Testing
- Inclusion Rating
- Ferrite Testing
- Porosity Testing
- Grain Flow Testing and Analysis
- Weld Testing
- X-Ray Diffraction (XRD) Analysis
- Scanning Electron Microscopy (SEM) Laboratory
- Harmful Substances Testing
- Reverse Engineering & Deformulation
- Industrial Problem Diagnosis
- Ingredient Analysis