Reporter:Chen-Kun Lin Adviser:Cheng-Chien Wang

Epoxy resins are widely used as coatings,adhesives,primers, semiconductor encapsulation and as matrices for advanced fibre-reinforced composites. Epoxy resin systems can be rendered fire retardant either by the incorporation of fire retardant additives (e.g. triphenyl phosphate,decabromo diphenylether, aluminium ethyl phosphinate ) or by copolymerisation with reactive fire retardants (e.g. diglycidylether of tetrabromobisphenol A ). Introduction

Among non-reactive compounds containing phosphorus, derivatives of 9,10-dihydro-9-oxa-10-phosphaphenanthrene- 10-oxide (DOPO)were shown to induce especially excellent flame retardant properties in both neat epoxy systems and their fibre-reinforced counterparts. Introduction

Experimental Preparation of neat epoxy formulations DGEBA was placed in a glass flask and heated to 80–90 ℃ using an oil bath connected to a temperature controller. The desired amount of the given hardeners was added slowly to the resin and subsequently the suspension was mixed using a mechanical stirrer operating at 600–1300 rpm until the compounds were dissolved and the mixtures were clear again. During mixing the temperature was kept constant at 80– 90 ℃. 60 vol.% of carbon fibres

Experimental

Following the mixing procedure, the hot mixtures were poured into a preheated aluminium mould at 80 ℃. Following the mixing procedure, the hot mixtures were poured into a preheated aluminium mould at 80 ℃. All epoxy formulations were cured as follows: the curing cycle started with a 2 ℃ min -1 rise from room temperature to 180 ℃. This temperature was maintained for 2 h and curing was completed with a 2 ℃ min -1 climb from 180 ℃ to room temperature. Evaluation of the decomposition behaviour& fire behaviour

Results and discussion Decomposition mechanism of the neat epoxy formulations

Results and discussion Fire behaviour of the neat resin formulations and of the carbon fibre-reinforced composites

Results and discussion Fire behaviour of the neat resin formulations and of the carbon fibre-reinforced composites

When 2 was substituted for DDS as a hardener for the neat epoxy resin system, the LOI was improved significantly; an increase of about 13% was achieved with a phosphorus content of 4.5 wt.%. A similar impact on flammability was also achieved for the composite based on DGEBA/DDS/2 with 60 vol.% carbon fibres and an overall phosphorus content of only around 1 wt.%. The LOI of the composite DGEBA/DDS/2 was increased by 17% and the UL 94 improved to a V-1 classification from the HB for the analogous DGEBA/DDS composite. Conclusions

Addition of 1 the PHRR and the THE were improved crucially due to flame inhibition,whereas the charring induced in the DGEBA/DDS/2 composites could not be exploited with respect to PHRR and THE. The incomplete combustion led to an increase in total smoke release (TSR) and in CO production. Conclusions

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