Most OEMs and system suppliers have similar require-ments for sunroof frames: low material distortion, high flexural modulus and excellent bonding with adjacent com-ponents, in addition to other specific OEM requirements.

Polyscope’s glass-reinforced XIRAN® SG grades offer a better combination of properties at a lower cost to meet OEM requirements than competitive plastics such as PBT/ASA, PBT, PA, PP and thermoset SMC, all of which are used in sunroof frames.

Cost analysisXIRAN® SG grades are the logical choice for current and future sunroof frame applications, thanks to an outstanding combination of benefits. The lower den-sity, excellent bonding to polyurethane (PUR) adhe-sives without primer or surface pre-treatment and the ability up to 20% recycled material make XIRAN® SG grades more cost effective than PBT/ASA-GF or PP LGF. Versus competitive engineering plastics, XIRAN® SG grades are the ideal solution for today’s larger sunroof frames.

Engineering Plastics

XIRAN® in sunroof frames

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XIRAN SG260 PP-LGF30 PBT/ASA GF30

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Technical and commercial benefits of XIRAN® SG grades• high dimensional stability • excellent adhesion without surface treatment • very-low warpage• high creep resistance• low density, high economic value• good chemical resistance• easy recyclablility with efficient waste streams

Properties of XIRAN® SG grades Charpy notched impact Charpy unnotched impact Flexural test Density (ISO 179/1eA) (ISO 1791eU) (ISO 178) (ISO 1183)

at +23°C at -40°C at +23°C at -40°C

flexural flexural

SI unit strength modulus

kJ/m² kJ/m² kJ/m² kJ/m² N/mm² N/mm² g/cm³

SG230 9 8 28 32 120 5400 1,1715% GF

SG240 10 9 30 35 132 6000 1,2020% GF

SG260 10 9 31 33 152 8500 1,2730% GF

Adhesion to PUR adhesive XIRAN® SG grades provide excellent adhesion with-out need for surface pre-treatment to PUR adhesives used to bond sunroof frames to sheet-metal roofs, whereas PC/ABS and PP have poor or limited adhesion to these adhesives without the cost and time of surface modification.

Creep under stressThe very low creep of XIRAN® SG grades ensures tight mechanical fixations and screw-torque retention over the part’s lifetime. XIRAN® SG grades creep signifi-cantly less than PP-LGF or PBT/ASA-GF. Fewer metal inserts are needed to secure a sunroof frame molded of XIRAN® SG.

Thermal performance XIRAN® SG grades offer excellent retention of proper-ties under temperature variations, e.g. shear modulus remains more stable than in semi-crystalline materials such as long-glass polypropylene (PP-LGF). Therefore, parts molded from XIRAN® SG grades experience less dynamic deformation at elevated temperatures.

Warpage and shrinkageComponents molded with amorphous XIRAN® SG grades exhibit much less warpage than with semi-crystalline materials (PP-LGF, PBT/ASA-GF, PBT-GF, PA-GF), minimizing “fit and finish” issues in the assembly and performance of sunroof modules.

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XIRAN SG230

Disclaimer: All information supplied by or on behalf of the Polyscope in relation to its products, whether in the nature of data, recommendations or otherwise, is supported by research and believed reliable, but Polyscope assumes no liability whatsoever in respect of application, processing or use made of the afore mentioned information or products, or any consequence thereof.

• Learn More: www.polyscope.eu or Info@polyscope.eu

About Polyscope Polymers Polyscope Polymers BV is the global leader in research, prod-uct development, and production of Styrene Maleic Anhy-dride (SMA) copolymers and compounds. As such, it offers the world’s broadest portfolio of neat, reinforced, and recy-cled SMA product lines. A global customer base is supported from corporate headquarters and production in Geleen, The Netherlands, and with local compounding and sales support in Europe, North America, and Asia.

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XIRAN SG230