The new adhesive, Crystic Crestomer 1153PA, is pre-accelerated and MEKP cured (2% w/v), and supplied in 25 kg and 200 kg containers as required. Scott Bader says the product is aimed at manufacturers of larger fibre reinforced plastic (FRP) structures (typically with dimensions over 25 m) which would benefit from an open working time of up to 90 minutes.
The longer working time of the adhesive is also of benefit to fabricators operating in ambient temperatures above 25°C. Customers can use the longer open time Crestomer 1153PA during the hottest summer months, switching to Crestomer 1152PA adhesive during the colder months of the year.
Scott Bader Crestomer structural adhesives are used by marine craft manufacturers in Europe, the Middle East, South Africa, America and China.
As with all products in the Crestomer range, Crestomer 1153PA was submitted to Lloyds Register for testing and gained Lloyds Acceptance (Statement of Acceptance MATS/1785/3), which covers structural adhesives for use in the most critical FRP bonding applications.
Crestomer 1153PA is reported to have excellent adhesion to FRP materials. Scott Bader quotes typical lap shear bond joint strengths for FRP to FRP of 10 MPa have been recorded under BS ISO 4587:2003, with the limiting factor being failure of the substrate not the adhesive.
This performance of the adhesive was demonstrated in 2009 when lifeboat manufacturer Schat-Harding set a new 55 m free fall drop world record for a lifeboat with its FF1200 model. The hull bulkheads in this boat's sandwich composite design were bonded using Crestomer 1152PA. The FF1200 was the first vessel to meet all the new OLF (Norwegian Oil Industry Association) design criteria for lifeboats in the Norwegian offshore sector.
The Scott Bader R&D team developed the Crestomer 1153PA adhesive by modifying the Crestomer 1152PA grade, which has been proven in use for over 20 years, specified by FRP leisure boat builders for a variety of hull and deck bonding applications. Also MEKP cured, the 1152PA product has a shorter open working time of 50 minutes. Both grades can be applied manually or using suitable dispensing equipment.
