One aspect of the invention relates to softwood lignin derivatives having an aliphatic hydroxyl content of from about 2.5 mmol/g to about 7 mmol/g lignin, and the preparation method thereof. The lignin derivatives have a desired antioxidant activity characterized by radical scavenging index (RSI). Another aspect of the invention relates to compositions comprising the softwood lignin derivative. Another aspect of the invention relates to a use of the softwood lignin derivatives comprising incorporating the softwood lignin derivatives into polymer compositions.