Derivatives of native lignin from annual fibre feedstocks
The present invention provides derivatives of native lignin having certain aliphatic hydroxyl content. Surprisingly, it has been found that consistent and predictable antioxidant activity may be provided by selecting for derivatives of native lignin having certain aliphatic hydroxyl content.
1. A thermoplastic composition comprising a thermoplastic polymer and an annual fibre lignin derivative, wherein said lignin derivative has an aliphatic hydroxyl content of from about 1 mmol/g to about 3.75 mmol/g, a normalized RSI of 15 or greater and a polydispersity of from about 1 to about 5.
2. The composition according to claim 1 , wherein the derivative has an aliphatic hydroxyl content is from about 1 mmol/g to about 3.25 mmol/g.
3. The composition according to claim 1 , wherein the derivative comprises alkoxy groups.
4. The composition according to claim 3 , wherein the alkoxy content is 0.1 mmol/g or greater.
5. The composition according to claim 1 , wherein the derivative has an aliphatic hydroxyl content is from about 1 mmol/g to about 3.25 mmol/g.
6. The composition according to claim 1 , wherein the derivative comprises ethoxy groups.
7. The composition according to claim 6 , wherein the ethoxy content is 1.4 mmol/g or less.
8. A polyolefin composition comprising an annual fibre lignin derivative, wherein said lignin derivative has an aliphatic hydroxyl content of from about 1 mmol/g to about 3.75 mmol/g, a normalized RSI of 15 or greater and a polydispersity of from about 1 to about 5.
9. The thermoplastic composition according to claim 1 , wherein the thermoplastic polymer is selected from the group consisting of polyethylene, polypropylene, polyamides, styrene-butadiene, and a combination thereof.