Professortechnical marketing consultant, University of Lowell, LowellRheometrics, Inc., Piscataway, MANJ
Pages: 20 Published: Jan 1984
Recently, members of the ASTM Subcommittee D20.10 on Mechanical Properties have authored ASTM Definition and Description of Terms Relating to The Dynamic Mechanical Properties of Plastics (D 4092) for identifying or characterizing the important rheological properties of plastics materials and composite systems. ASTM Dynamic Mechanical Properties of Plastics (D 4065), which is being developed currently, addresses the specific procedures that are to be used in measuring these important viscoelastic properties. The study of rheology is of special interest to scientists and engineers since it identifies important macromolecular characteristics that affect the functional properties of a fabricated part, such as an injection molded steering wheel, an iron oxide coating on a magnetic recording tape, or a high strength epoxy/graphite helicopter rotor blade. In every case the quality of the incoming material, the effect of processing, and the quality of the final functional part are equally important. ASTM D 4065 and D 4092 address these needs and provide meaningful information for establishing and monitoring quality control/assurance procedures.
The review of the major features of ASTM D 4065 and selected case studies will illustrate how rheological measurements have been used in quality control/quality assurance (QC/QA) programs. Results for thermoplastics and thermosetting resins are presented, including typical additives. Dynamic mechanical properties are provided as functions of frequency (dynamic oscillation), strain, temperature, and time. Additionally, thermosetting prepregs shall be studied for the effect of cure mode, rate of heating, and post-cure thermal treatments.
The importance of ASTM D 4065 and D 4092 definitions are emphasized in the discussions.
plastics, rheology, plastic processing, thermosetting resins, curing, rheological measurements, dynamic mechanical properties, curing behavior, thermoplastics
Paper ID: STP33231S