You entered the kitchen to prepare tea for yourself. On seeing you wearing synthetic clothes, your mother drove you out of the kitchen and asked you to change and come back. Think of the possible reason for your mother to react in such a manner.
Synthetic fibres catches fire easily and starts melting, and sticks to the body which maybe lead to severe burning. Wearing synthetic clothes to kitchen can lead to severe accident and so you will always observe that people who spend an ample amount of time in kitchens and laboratory often wear cotton but never synthetic.