1st PRIMaRE conference, Plymouth, 04-05 June 2014

Zoltán Gombos and John SummerscalesAdvanced Composites Manufacturing Centre (ACMC)

Centre for Advanced Engineering Systems and Interactions research group (CAESI)University of Plymouth

Abstract

Fibre-reinforced polymer composites are used in many applications in themarine environment because of their excellent durability. Thisperformance is often enhanced by the use of a surface coating (normallyan unsaturated polyester or vinyl ester polymer-rich gel-coat). Gel-coatshave traditionally been applied by hand-painting or spraying whichreleases styrene (a reactive diluent in the resin) into the workplace andthe environment. The FP7 InGeCt project has developed two in-mouldgel-coating systems. This paper compares the conventional hand-paintedgel-coating, in-mould gel-coating with a separator fabric (IMGC) and in-mould surfacing (IMS) with a silicone shim to establish if styrene levels canbe significantly reduced by the adoption of closed mould systems.

Conclusions

The conventional hand-painted technology was found to have significantlyhigher levels of styrene emission than the two closed mould processes. Forthe open mould process, the average styrene levels were in the range 28-70ppm. The two closed mould technologies significantly reduce the measuredstyrene levels to lie in the range 0.23–0.37 ppm. The new processes offer areduction in average styrene emission levels of >98% (worst new/best old).This has obvious benefits for worker health and the reduction ofenvironmental burdens.

Acknowledgement

This research is funded by the European Union's Seventh FrameworkProgramme managed by REA-Research Executive Agency ([FP7/2007-2013] [FP7/2007-2011]) under grant agreement number FP7-SME-2011-1-286520. The partner companies were:• Alan Harper Composites (Cornwall)• Centro Tessile Cotoniero E Abbigliamento SpA (IT)• De IJssel Coatings BV (NL)• KMT Nord APS (DK)• Lightweight Structures BV (NL)• SP Technical Research Institute of Sweden (SE)• Tessitura Valdolona SRL (IT)

Styrene level HPGC RTM/IMGC RIFT/IMS

IMGC TWA (ppm) 71 0.24 (-99.7%) N/A

IMGC Ceiling (ppm) 1017 36 (-96.5%) N/A

IMS TWA (ppm) 29 0.23 (-99.2%) 0.37 (-98.7%)IMS Ceiling (ppm) 668 49 (-92.6%) 107 (-84.0%)

Table 1: Styrene levels (andpercentage reductions) using the in-mould gel-coating techniques

Hand-painted Separator fabric Silicone shim

upper images : flat plate, lower: complex geometryNB: extended scales for hand-painted plates

Gel-coating for marine structures