Abstract: Bamboo fiber was surface modified with isocyanate (MDI) and used to reinforce poly(lactic acid) through injection molding. Interface, mechanical, and thermal properties of the resulted composites were investigated. As MDI addition increased, tensile strength of composites gradually increased，impact strength first increased and then decreased. When MDI addition was 1.5 %, tensile strength and impact strength of composites reached the maximum of 63.4 MPa and 11.3 kJ/m2, respectively. The storage modulus of composites gradually increased, loss factor gradually decreased, glass transition temperature, crystallization temperature and pyrolysis temperature of composites increased, thermal stability of composites increased with increasing MDI content.

Key words: composites, interface modification, bamboo fiber, poly（lactic acid）, isocyanate, mechanical property