{'fraction_non_alphanumeric': 0.06234413965087282, 'fraction_numerical': 0.008728179551122194, 'mean_word_length': 5.224806201550388, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Synthesis and Characterization of Amphiphilic Triblock Copolymers Poly(N~ε-CBZ-Lysine)-PEG-Poly(N~ε-CBZ-Lysine)

Lys(z)-NCA was synthesized from N e-carbobenzoyloxy-L-Lysine and triphosgene in THF. Amphiphilic triblock copolymers poly(N e-carbobenzyloxy-L-Lysine)(poly(N e-CBZ-Lysine)-PEG-poly(N e-CBZ-Lysine)) were synthesized in DMF in the condition that both amino-end PEG was used as initiator. The structures of the block copolymers were characterized by IR, 1H NMR, GPC and DSC. The results revealed that triblock copolymers with controlled M n and narrow molecular weight distribution(I p=1.06) were synthesized, the yield was 95.4%. These block copolymers are expected to have promising application in the field of biomaterials for the two components in block copolymers are both biocompatible.