In contrast to conventional isoprene and butadiene

1

3-pentadiene monomer can undergo anionic copolymerization to afford special sequence controlled copolymers

such as alternating copolymers. In this paper

a series of binary and ternary copolymers were synthesized using 1

3-pentadiene

styrene and p-tert-butylstyrene comonomers and initiated by n-butyllithium. Focusing on the copolymerization kinetics and microstructure of copolymers

some interesting results were obtained: (1) kinetics analysis indicated that copolymerization conformed to the characteristics of classical primary reactions

and all comonomers can be converted completely; (2) the real-time NMR analysis showed the equal consumption of pentadiene and its comonomer

and

1

HNMR/

13

C-NMR spectra all proved the binary alternating sequence structure; (3) binary and ternary copolymerization had obvious living and controllable polymerization characteristics

the molecular weight was highly consistent with the theoretical value

and the molecular weight distribution

D

was less than 1.20; (4) the DSC results showed that copolymers were a special class of semi-crystalline polymers

and the glass transition temperature

T

g

can be fine-tuned by regulating the proportion of comonomers

and

T

m

is in the range of 100-120 ℃; (5) Based on dual-alternating copolymerization strategy of pentadiene

we proposed the possible alternating polymerization mechanism.