Resin infusion technology

A lead adopter, at least among production boat builders, of new resin film infusion materials is the French company Poncin Yachts, which offers hulls laid up in SP Systems Resin Infusion Technology (SPRINT) material. The company could equally have chosen Hexcel Composites HexFit, or another of the several semi- preg products now available on the market. 

Ness D, Jones DT, SP resin infusion technology (SPRINT), FRC2000 Conference, Newcastle, Sep 13-14, 2000. 

SP Systems, SPRINT SP resin infusion technology. Advantage Magazine, 4-5, Jan 2001. 

Resin infusion technology is a process using a dry fibre laminate preform. A dry stack of fabric material is placed into a mould tool the fabric is sometimes... 

SPRINT allows heavier weight reinforeement to be used when compared with prepreg technology and conforms readily during proeessing. Resin flow is more easily eontrolled than in the resin infusion process and the resin only has to flow through the thickness of the fiber to achieve full impregnation. 

Blest DC, McKee S, Zulkifle AK, Marshall P. Curing simulation by autoclave resin infusion. Composites Science and Technology, 1999 59(16) 2297—2313. DOI http //dx.doi.org/10.1016/S0266-3538(99)00084-6. 

Acid-curing resoles can be processed by hand-lamination, spray-up lamination, winding, and by infusion-technology, as well as by processes familiar from fiber-composite polymer (FCP) technology. Acid-resistant machine components and molds have to be used, and the shorter open times compared to polyester resins have to be taken into consideration. Compression processing, which is suitable for novolacs and resoles, requires ventilation strokes — as in most processing methods with closed molds - to let the developing water vapor escape. 

The formation of crosslinked networks has been the basis for polymer technology since the development of phenol-formaldehyde resins by Baekeland in 1910. The changes to the rheology of the phenolic system, as it develops from a liquid to a rubber and then to a glass, arise from the formation of a three-dimensional network as the step-growth chemical reactions occur. Water is evolved and the end product is a solid infusible mass. 

However, the above operations show some disadvantages compared to more advanced manufacturing technologies first of all, hand lay-up of fibers requires a greater quantify of resin than normally necessary. Secondly, eliminating the superfluous part turns out to be quite a hard operation, even by means of a vacuum infusion and, as a result, the composite will be of worse qualify, since very mobile fiber layers increase the difficulty in executing a good vacuum bag. 

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