Towards microphase separation in epoxy systems containing PEO/PPO/PEO block copolymers by controlling cure conditions and molar ratios between blocks. Part 2. Structural characterization

The mechanical properties were investigated of a series of PA-PEG thermalplastic elastomer based on PA1010 and polytetramethylene glycol (PEG) with varying hard and soft segment content. Dynamic mechanical measurements of these polymers have carried out over a wide range of temperatures. The block copolymers exhibit three peaks, designated as α, β and γ in the tanδ-temperature curve. The α transition shifts to higher temperature with increasing hard block molecular weight. However, at a constant hard molecular weight, the α transition shifts to higher temperature and the damping increases on increasing the soft segment molecular weight. DMA results show that the block copolymers exhibit a microphase separation structure and both soft and hard segments were found to be crystallizable. The degree of phase separation increases with increasing hard block molecular weight.

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Phase behaviors of side chain liquid crystalline block copolymers

RSC Advances ◽

10.1039/c4ra11585f ◽

2015 ◽

Vol 5 (2) ◽

pp. 1514-1521 ◽

Cited By ~ 8

Author(s):

Xiaokang Li ◽

Feng Huang ◽

Tao Jiang ◽

Xiaohua He ◽

Shaoliang Lin ◽

...

Keyword(s):

Block Copolymers ◽

Liquid Crystalline ◽

Microphase Separation ◽

Dissipative Particle Dynamics ◽

Particle Dynamics ◽

Side Chain ◽

Phase Behaviors

The microphase separation of side chain liquid crystalline (SCLC) block copolymers was studied using dissipative particle dynamics (DPD) simulations.

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Synthesis and microphase separation of polystyrene-b -polylactide block copolymers aimed at preparation of ordered nanoparticle/block copolymer hybrid materials

Polymer International ◽

10.1002/pi.4746 ◽

2014 ◽

Vol 63 (7) ◽

pp. 1159-1167 ◽

Cited By ~ 6

Author(s):

Xiaodong Hou ◽

Qiaobo Li ◽

Amin Cao

Keyword(s):

Block Copolymer ◽

Block Copolymers ◽

Hybrid Materials ◽

Microphase Separation

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Microphase Separation (of Block Copolymers)

Encyclopedia of Polymeric Nanomaterials ◽

10.1007/978-3-642-36199-9_149-1 ◽

2014 ◽

pp. 1-6 ◽

Cited By ~ 1

Author(s):

Yushu Matsushita

Keyword(s):

Block Copolymers ◽

Microphase Separation

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The Latest Development of the Weak Segregation Theory of Microphase Separation In Block Copolymers

Nanostructured Soft Matter - NanoScience and Technology ◽

10.1007/978-1-4020-6330-5_11 ◽

2007 ◽

pp. 327-370 ◽

Cited By ~ 8

Author(s):

Igor Erukhimovich

Keyword(s):

Block Copolymers ◽

Microphase Separation

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Block Copolymers, Structural Characterization of

Encyclopedia of Materials: Science and Technology ◽

10.1016/b0-08-043152-6/00141-8 ◽

2001 ◽

pp. 733-738

Author(s):

S.P. Gido

Keyword(s):

Block Copolymers ◽

Structural Characterization

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PPG-Terminated Tetra-Carbamates as the Toughening Additive for Bis-A Epoxy Resin

Polymers ◽

10.3390/polym11091522 ◽

2019 ◽

Vol 11 (9) ◽

pp. 1522

Author(s):

Ming Zhang ◽

Mingqing Chen ◽

Zhongbin Ni

Keyword(s):

Epoxy Resin ◽

Epoxy Matrix ◽

Microphase Separation ◽

Intramolecular Interactions ◽

Hexamethylene Diisocyanate ◽

Separation Mechanism ◽

Toughening Mechanism ◽

The Impact ◽

Modified Epoxy ◽

Epoxy Systems

We synthesized PPG-terminated tetra-carbamates as a new toughening additive for epoxy thermosets through facile addition reaction of hexamethylene diisocyanate (HDI) with poly(tetra-methylene glycols) (PTMG) and poly(propylene glycols) (PPG). The effects of prepared tetra-carbamates on the rheological behavior of neat epoxy resin were studied along with the various cured properties of their modified epoxy systems. Four carbamate groups (–NHCOO–) endow the prepared additives not only with good intramolecular interactions, but also with optimal intermolecular interactions with epoxy polymers. This results in the suitable miscibility of the additives with the epoxy matrix for the formation of the typical biphasic structure of microparticles dispersed in the epoxy matrix via polymerization-induced microphase separation. The impact strength and critical stress concentration factor (KIC) of cured modified epoxy systems with the additives are significantly higher than those of unmodified epoxy systems, without sacrificing the processability (Tg) and flexural strength. The toughening mechanism is understood as a synergism combination among the phase separation mechanism, the in situ homogeneous toughening mechanism, and the particle cavitation mechanism.

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