scholarly journals Crystallization of Block Copolymers IV. Molecular Weight Dependence of the Morphology Formed in ε-Caprolactone–Butadiene Diblock Copolymers

1995 ◽  
Vol 27 (7) ◽  
pp. 673-682 ◽  
Author(s):  
Shuichi Nojima ◽  
Satoru Yamamoto ◽  
Tamaichi Ashida
Keyword(s):  
Molecular Weight ◽  
Block Copolymers ◽  
Diblock Copolymers ◽  
Molecular Weight Dependence

Molecular weight dependence of lamellar domain spacing of diblock copolymers in bulk

1990 ◽  
Vol 23 (19) ◽  
pp. 4313-4316 ◽  
Author(s):  
Yushu Matsushita ◽  
Katsuaki Mori ◽  
Ryuichi Saguchi ◽  
Yasushi Nakao ◽  
Ichiro Noda ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Diblock Copolymers ◽  
Molecular Weight Dependence

Bulk and solution properties of a thermo-responsive rod–coil block polymer based on poly(N-isopropylacrylamide)

RSC Advances ◽  
2014 ◽  
Vol 4 (90) ◽  
pp. 49028-49039 ◽  
Author(s):  
Peng Liu ◽  
Jiexing Liang ◽  
Shen Chen ◽  
Hailiang Zhang
Keyword(s):  
Molecular Weight ◽  
Diblock Copolymers ◽  
Solution Properties ◽  
Block Polymer ◽  
Molecular Weight Dependence

Molecular weight dependence on thermoresponsive behaviors of rod–coil diblock copolymers (x indicates the DP of rod PHIPPVTA blocks).

Block Copolymers Poly(2,6-dimethyl-1,4-phenylene oxide)-poly(6-hexanelactam). Preparation and Composition

1993 ◽  
Vol 58 (11) ◽  
pp. 2574-2582 ◽  
Author(s):  
Jaroslav Stehlíček ◽  
Rudolf Puffr
Keyword(s):  
Molecular Weight ◽  
Block Copolymers ◽  
Diblock Copolymer ◽  
Anionic Polymerization ◽  
Diblock Copolymers ◽  
Toluene Solution ◽  
Low Molecular Weight ◽  
Phenylene Oxide ◽  
End Groups ◽  
Tolylene Diisocyanate

Poly(2,6-dimethyl-1,4-phenylene oxide)-poly(6-hexanelactam) diblock copolymers were prepared from low-molecular weight poly(2,6-dimethyl-1,4-phenylene oxide) by transforming its phenolic end groups via the reaction with 2,4-tolylene diisocyanate and 6-hexanelactam to polymeric initiators and the subsequent anionic polymerization of 6-hexanelactam. The polymerization of 6-hexanelactam was carried out in bulk or toluene solution. The content of the 6-hexanelactam homopolymer was estimated by TLC showing that the pure diblock copolymer can be prepared in toluene. The reason for relatively low yields is discussed.

Distribution of molecular weight and composition in diblock copolymers

e-Polymers ◽  
2003 ◽  
Vol 3 (1) ◽  
Author(s):  
Hidetaka Tobita ◽  
Shiping Zhu
Keyword(s):  
Molecular Weight ◽  
Block Copolymers ◽  
Theoretical Analysis ◽  
Diblock Copolymers ◽  
Weight Fraction ◽  
Bivariate Distribution ◽  
Chemical Compositions ◽  
Composition Distribution ◽  
Average Composition ◽  
Insight Into

Abstract The distribution of molecular weight (MW) and composition of diblock copolymers is considered theoretically. Assuming that the chain end of each block is coupled randomly, the weight-average MW of the block copolymers is given by Mw = w1 (Mw,1 + Mn,2) + w2 (Mw,2 + Mn,1), irrespective of the shape of the distribution of each block, where wi is the weight fraction, and Mn,i and Mw,i are the number- and weight-average MW of each block. In copolymer chains, the chemical compositions as well as the MWs cannot be identical for all polymers, and there exists a bivariate distribution of MW and composition. When the MW distribution (MWD) of both blocks follows the Schulz-Zimm distribution, the bivariate distribution can be obtained analytically. In addition to the bivariate distribution, the full MWD, the average composition as a function of MW, the composition distribution of copolymers having a specified MW, and the overall composition distribution are obtained. The composition distribution, as well as the average composition, becomes independent of MW under the condition σ1/Mn,1 = σ2/Mn,2, where σ i is a parameter indicating the narrowness of the Schulz-Zimm distribution. The present theoretical analysis provides new insight into the design of diblock copolymers.

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