In this study, the possibility of using limonene for surface modification of poly ethylene terephthalate (PET) fabric was investigated to improve its wettability as well as reducing and eliminating chemical waste. Limonene is a naturally hydrocarbons which knows as a green solvent, antibacterial sensible, natural fragment and flavor. It is commonly found in citrus fruits such as oranges, lemon and citrus aurantium. In the first part of this project, essential orange peel oil was optimized by water distillation extraction method and then value of limonene in essential oil was determined by GC-MS method. In the second part, emulsion of limonene oil in macro and Nano dimensions was prepared in order to provide a homogenous condition for surface modification treatment. In this part, limonene oil in water Nano emulsion successfully produced with high stability more than 5 month and particle size less than 10 nm which is a significant achievement for industry applications. In the third part, polyester fabric was treated by limonene oil in water macro emulsion in Polymat at specified conditions and various concentrations. Efficiency of treatment was evaluated by some experimental such as vertical wicking height, water absorption time, moisture regain and resistance conductivity. Results showed that wettability properties was improved after treatment whereas tenacity was reduced. In the fourth part, limonene was used at the same time with other surface modification conditions such as modification under UV, Ozone and UV/Ozone and then results were compared with each other. Surface modification by limonene under UV radiation in one step is suggested as optimum method. Results showed that wettability properties of fabric were improved after treatment by limonene/UV whereas tenacity was increased due to cross-linking during possibility radical reactions that confirmed by FTIR-ATR spectrum so that intensity of C-O-C peak increased. To evaluate the structural changes occurred on the sample by limonene/UV, the electron microscopy image, Fourier transform infrared spectroscopy and the absorption of methylene blue dye were examine. SEM image showed that corrosion on the surface of fabric was occurred that is related to the polymer chain failure, these changes cause increasing of functional group like carboxylic acid and hydroxyl group which were confirmed by FTIR-ATR spectrum. The formation of carboxylic acid group and surface limited treatment is also confirmed by increasing in absorption of methylene blue only on one side of the fabric. In the last part, effect of oil particle on surface modification of PET was investigated, results of wettability tests and staining methylene blue dye experiment showed that Nano emulsion has a better performance in surface modification, but this was not very significant.
