Crosslinking of polyamide materials

The aim of this thesis work is partially crosslinking the commercial polyamide, 6 (PA 6) with chemical crosslinking techniques and to suggest different models of PA. Main reason for crosslinking the PA is to improve its creep resistance, since it is a good alternative to metals in variety of applications especially in automotive industry. Firstly, in order to crosslink the commercial polyamide, two different crosslinking agents was used which are commercially known Primid® XL-552 and Primid® QM-1260, and two different methods were studied to obtain a homogeneous mixture of PA and cross-linkers. Crosslinking reactions were performed by thermal treatment. Final products were analyzed using thermal characterization techniques (differential scanning calorimetry and thermal gravimetric analysis). Moreover, solubility test of cross-linked PA was performed by using sulfuric acid and as a result, product dissolved in sulfuric acid which implies crosslinking did not occur. Secondly, model of hyper-branched PA with high amount of functional groups was synthesized using trimellitic anhydride and hexamethylene diamine sd monomers. Composition of the reaction product was analyzed with IR spectrum in addition to thermal characterization techniques and solubility test. Crosslinking of the hyper-branched PA justified by solubility test of the reaction product in dimethyl sulfoxide. Lastly, low molecular weight PA 6,6 was successfully synthesized from monomers adipic acid and hexamethylene diamine. Furthermore, crosslinking of LW PA was performed by thermal treatment. Determination of the crosslinking was made by using dimethyl sulfoxide as solvent at 150°C.