Performance and Quality of KIA MS237-12 POM (Polyoxymethylene) Material

The standard “KIA MS237-12 Performance and Quality of POM (Polyoxymethylene) Material” developed by Hyundai-Kia Motors Company, the oldest motor vehicle manufacturer in Korea, describes a procedure for determining the performance and quality of polyoxymethylene (POM) material used in the production of vehicles. This material is usually used in interior parts to reduce odor or as indicated on drawings. The classification of polyoxymethylene is given in the table titled “Types and Applications” given in the standard:

• Type A: General purpose (HVAC lever, accelerator pedal, kick down pedal)
• Type B: Light resistance (seat belt buckle, knob)
• Type C1: Impact resistance (20 percent polyurethane) (clips, fasteners)
• Type C2: Impact resistance (10 percent polyurethane) (clips, fasteners)
• Type D: High fluidity (speaker grille)

The general requirements in this standard are described as follows:

• Parts using this material must comply with all requirements of the relevant assembly performance standard.
• The chemical composition and processing conditions should not be changed inappropriately, which may affect the quality of the parts.
• Before changing the chemical composition of the material, it is mandatory to consult with the materials and quality control departments.
• Final parts made from this material must be free from defects, uneven shine, burn marks, warpage, silver streak, cracks, uneven color, flow marks, weld lines, sink marks or other defects.
• The melting temperature should be below 200 degrees and the residence time during injection molding should be less than 5 minutes.

This material is tested by the methods defined in the standard and must comply with the conditions specified in the table.

In general, the standard condition of the laboratory in the tests is 23 degrees plus/minus 2 degrees temperature and 50 percent plus/minus 5 percent relative humidity. The samples are carried out on the samples immediately after a conditioning period of at least 48 hours in the standard condition specified above at least 24 hours after molding.

The following standards are followed for melt index:

• “ISO 1133 Plastics - Determination of melt mass flow rate (MFR) and melt volume flow rate (MVR) of thermoplastics”.
• “ASTM D1238-10 Standard test method for melt flow rates of thermoplastics by extrusion plastometer”.

The following standards are followed for specific gravity:

• “ISO 1183-1 Plastics - Methods for determining the density of non-cellular plastics - Part 1: Immersion method, liquid pycnometer method and titration method”.
• “ASTM D1505-18 Standard test method for density of plastics based on density gradient”.

The following standards are followed for tensile strength and elongation:

• “ISO 527-1 Plastics - Determination of tensile properties”.

The following standards are followed for sample type:

• “ISO 3167 Plastics - Multi-purpose test specimens” (specimen type Type A, test speed 50 mm/min).
• “ASTM D638-14 Standard test method for tensile properties of plastics” (specimen type Type 1, test speed: 50 mm/min).

The following standards are followed for flexural strength and modulus:

• “ISO 178 Plastics - Determination of flexural properties” (specimen size 80,0 × 10,0 × 4,0 mm, span length 64 mm, test speed: 2 mm/min).
• “ASTM D 790 Standard test methods for flexural properties of unreinforced and reinforced plastics and electrical insulating materials” (specimen size 127,0 × 12,7 × 6,4 mm, test speed: 30 mm/min).

The following standards are complied with for Izod impact resistance:

• “ISO 180 Plastics - Determination of Izod impact strength” (sample type Type A, sample size 80 × 10 × 4,0 mm (notched), hammer 2,94 J).
• “ASTM D256-23 Standard test methods for determining the Izod pendulum impact resistance of plastics” (specimen size 63,5 × 12,7 × 6,4 mm (notched), hammer 2,94 J).

The following standards are followed for Rockwell hardness:

• “ISO 2039-2 Plastics - Determination of hardness - Part 2: Rockwell hardness”.
• “ASTM D 785 Standard test method for Rockwell hardness of plastics and electrical insulating materials” (specimens R scale).

The following standards are followed for thermal distortion temperature:

• “ISO 75-1 Plastics - Determination of deflection temperature under load” sample size 80 × 10 × 4,0 mm, flat method, tensile load: 0,45 MPa)”.
• “ASTM D648-06 Standard test method for deflection temperature of plastics under bending load in axial position” specimen size 127 × 12,7 × 6,4 mm, tension load 0,45 MPa”.

The following standard is complied with for fade resistance:

• “KIA MS210-05 molded plastic parts - Interior”.

For volatile organic compounds (VOC), the following standard is complied with:

• “KIA MS300-55 Test method for determination of VOC emission from vehicle part”.

The following standard is followed for Fourier transform-infrared spectroscopy (FT-IR) :

• FTIR spectroscopy: Attenuated total reflection, measuring range 4.000 ~ 650 cm-1, scanning number 32 times).

The following standards are followed for the thermal gravimetric analyzer (TGA):

• “ISO 11358 Plastics - Thermogravimetry (TG) of polymers”.
• “ASTM E1131-08 Standard test method for compositional analysis by thermogravimetry” (heating rate 20 degree/min, temperature range room temperature ~ 850 degree).

The following standards are followed for differential scanning calorimetry (DSC):

• “ISO 11357 Plastics - Differential scanning calorimetry (DSC)”
• “ASTM D3418-21 Standard test method for transition temperatures and enthalpies of fusion and crystallization of polymers by differential scanning calorimetry” (heating and cooling rate 20 degrees/min).

For each test item described in this standard, the test report must be submitted to the relevant material team and quality control departments. Whenever materials, recycling and suppliers are changed, the test report must be submitted and approved.

Our organization has a strong staff that closely follows the developments in the world in the field of science and technology and constantly improves itself. Among the numerous test, measurement, analysis and evaluation studies provided for businesses in various sectors, there are also test services in accordance with the "KIA MS237-12 POM (Polyoxymethylene) material performance and quality" standard.