Polycarbonate-polysiloxane copolymer resin composition with high impact strength at low temperature and mechanical strength and method for preparing the same

A polycarbonate resin composition with high impact strength at low temperature and high mechanical strength, comprising:

• (A) about 100 parts by weight of a thermoplastic polycarbonate resin;
• and
• (B) about 0.1 to about 30 parts by weight of an organic siloxane polymer having a primary amine group, wherein said organic siloxane polymer having a primary amine group (B) is represented by following Chemical Formula 2:
• wherein:
• each R1 is independently C1-8 alkyl, C6-30 aryl, or C1-C15 alkyl-substituted C6-30 aryl;
• R2 is C1-8 alkylene;
• each R3 is independently hydrogen, C1-8 alkyl, C6-30 aryl, or C1-C15 alkyl-substituted C6-30 aryl;
• each p is independently 0 or 1;
• k is an integer from 1 to 5;
• and
• m and n are repeating units, wherein the ratio of m to n of said organic siloxane polymer having a primary amine group is about 99.5:0.5 to about 55:45;
• and
• (C) about 0.1 to about 10 parts by weight of an impact modifier.