Carbon Fiber Reinforced Plastics (CFRP)

Shimadzu provides instrumentation to assist in the development and production of carbon fiber reinforced plastics (CFRP) and other high performance, lightweight composites. Shimadzu instruments are used to measure the chemical, thermal and mechanical properties of fibers and matrix component plastics, resins, and additives.

CFRP Quality Control
Evaluation of the Degradation of a Resin Surface via FTIR
In addition to of heating, organic solvents, and acidic or alkaline solutions, resins may be denatured or degraded by ultraviolet rays. Durability against ultraviolet rays is particularly necessary for resin products that are used outdoors. Accordingly, in this test, acrylonitrile-butadiene-styrene (ABS) resins were exposed to ultraviolet rays and then analyzed by FTIR.
The surface of the ABS resin exposed to ultraviolet rays was measured with the single reflection ATR method, and changes in the infrared spectrum were investigated. The results show that O-H and C=O stretching vibrations caused an increase in absorption, i.e. progression of oxidation, with increasing ultraviolet exposure time. Furthermore, a reduction in the 966 cm-1 peak can be seen, indicating absorption due to =C-H out-of-plane deformation vibrations of the transvinylene group contained in the butadiene. Striking changes are not evident in peaks due to the stretching vibrations of the nitrile group -C≡N or the styrene C=C bonding. These results indicate that oxidation of ABS resins progresses from their butadiene parts due to the impact of ultraviolet rays.

FTIR Single Reflection ATR Method

In the single reflection ATR method, the sample is put in close contact with the surface of a prism with a diameter of approximately 2 mm, and the infrared spectrum is then measured. In addition to flat samples, this method can be applied to samples with curved surfaces and powdered samples. A liquid sample can also be measured by simply placing a drop of it on the prism.

The following shows a photograph of the external appearance of the IRAffinity-1 Fourier Transform Infrared Spectrophotometer equipped with the MIRacle10 Single Reflection ATR Attachment, as well as a schematic diagram of the optical system. When the infrared light shining from the prism is reflected at the interface between the prism and the sample, information is obtained about the sample surface (to a depth of approximately 1µm). Accordingly, not only is sample dilution and other pre-treatments unnecessary, but information regarding the sample surface is easily obtained.

Evaluation of CFRP Thermal Characteristics
With thermal analysis instruments, a variety of physical and chemical changes, including fusion, transition, crystallization, expansion, contraction, decomposition, and combustion, are measured while the sample is heated or cooled. Typical methods include DSC, TGA, and TMA, which are effective in evaluating the thermal properties of thermoplastic resins, thermosetting resins, and composite materials.

Differences in thermal flow to a standard substance and sample during heating (temperature differences) are measured to evaluate the temperatures at which fusion, transition, crystallization, and chemical reactions occur as well as changes in heat quantity.

  • Stable baseline over a wide temperature rang
  • High-sensitivity, high-resolution sensor
  • Equipped with a liquid nitrogen cooling tank

The hardening reaction of an epoxy resin used as a matrix was evaluated using DSC. The glass transition of an untreated sample was observed at -39.1 °C, after which significant heat generation due to the hardening was measured, with a peak of 118 °C. Little heat was generated by a sample treated for 5 minutes at 100 °C, since hardening had already progressed. Furthermore, heat generation was not observed in a sample treated for 60 minutes, since hardening was essentially complete. In this way, DSC enables the investigation of the relationship between heat treatment and hardening progression. In addition, it is evident that as hardening progresses, the glass transition shifts to higher temperatures.

Evaluating Strength of Reinforced Plastics Used for Bumpers
A variety of resin materials have been developed that, compared to conventional materials, are lightweight, strong, weatherproof, and increasingly in demand. One characteristic of these materials is the use of high-function fibers (light, strong, non-deforming, corrosion and heat resistant), including carbon fiber reinforced plastics (CFRP) and glass fiber reinforced plastics (GFRP). In the CFRP evaluation shown here, Poisson's ratio was obtained using a displacement measurement device to measure longitudinal strain, and a width sensor to measure transverse strain. Compared to soft iron and rubber, values from this type of material are one digit smaller, and the amount of distortion is very small.

Analysis/Measurement/Inspection  Evaluation Items Analysis/Testing/Inspection Evaluation Instruments
Static Test Tensile, bending, compression, peeling (adhesive strength/surface treatment evaluation), interlaminar shear Autograph AG-X plus Series Precision Universal Testing Machine
MCT Series Micro Compression Testing Machine
Impact Test High-speed tensile, puncture Hydroshot HITS Series High-Speed Puncture Impact Testing Machine
Fracture Observation Matrix fracture, fiber fracture, peeling HyperVision HPV-X2 High-Speed Video Camera
Thermal Analysis Glass transition, melting point, coefficient of thermal expansion, curing reaction DSC-60 Plus Differential Scanning Calorimeter
TGA-50/51 Thermogravimetric Analyzers
DTG-60 TG/DTA Simultaneous Measuring Instrument
TMA-60 Thermomechanical Analyzer
Composition Analysis Matrix resin, additives, elemental analysis, carbon fiber level GC/GC-MS Applied System
ICPE-9800 ICP Emission Spectrometer
IRAffinity-1s Fourier Transform Infrared Spectrophotometer
TGA-50/51 Thermogravimetric Analyzers
DTG-60 TG/DTA Simultaneous Measuring Instrument
Viscosity Measurement Thermosetting resin reactivity evaluation, thermoplastic resin injection molding evaluation CFT Flowtester
Degradation Evaluation Weather resistance, heat resistance IRAffinity-1s Fourier Transform Infrared Spectrophotometer
TGA-50/51 Thermogravimetric Analyzers
DTG-60 TG/DTA Simultaneous Measuring Instrument