以SEBS(苯乙烯-乙烯-丁烯-苯乙烯共聚物)、SBS(苯乙烯-丁二烯-苯乙烯共聚物)、丙烯酸酯、环保型溶剂和过氧化二苯甲酰(BPO)等为原料,制备出SEBS/SBS基胶粘剂,并着重考察了SEBS掺量对胶粘剂的黏度、光学性能、电性能、力学性能及粘接性...以SEBS(苯乙烯-乙烯-丁烯-苯乙烯共聚物)、SBS(苯乙烯-丁二烯-苯乙烯共聚物)、丙烯酸酯、环保型溶剂和过氧化二苯甲酰(BPO)等为原料,制备出SEBS/SBS基胶粘剂,并着重考察了SEBS掺量对胶粘剂的黏度、光学性能、电性能、力学性能及粘接性能等影响。研究结果表明:当w(SEBS)=5%~25%(相对于基体树脂总质量而言)时,胶粘剂的黏度适中,适合施工操作;当w(SEBS)=15%时,胶粘剂的接枝率、接枝效率(分别为17.11%、87.43%)相对最大,而单体转化率(为97.17%~98.36%)则变化不大;随着SEBS掺量的增加,胶粘剂的剪切强度或180°剥离强度呈先升后降态势,并且在w(SEBS)=25%或30%时相对最大(为1.87 MPa或1.73 k N/m),而且与不加SEBS体系相比分别增加了24.67%、140.28%。展开更多
The temperature-induced molecular chain motions of styrenic triblock copolymers (SBC), i.e. polysty- rene-block-polybutadiene-block-polystyrene (SBS) and polystyrene-block-poly(ethylene-co-l-butene)-block-poly- ...The temperature-induced molecular chain motions of styrenic triblock copolymers (SBC), i.e. polysty- rene-block-polybutadiene-block-polystyrene (SBS) and polystyrene-block-poly(ethylene-co-l-butene)-block-poly- styrene (SEBS), were studied by intrinsic fluorescence method. For SBS, the glass transition temperatures (Tgs) of B block and S block obtained by intrinsic fluorescence method were in good agreement with differential scanning calorimetry measurements (DSC). In the case of SEBS, an isoemission point was observed at about 310 nm at ele- vated temperatures, suggesting the slight conversion between the monomer and excimer emission. On this basis, the molecular chain motion of SEBS was monitored by both fluorescence intensity and excimer/monomer fluorescence ratio. Besides the Tgs of S block and EB blocks, a melting point (Tin) of weak crystalline in EB block was unambiguously determined by intrinsic fluorescence. Furthermore, it was found that the melting process directly led to the slight loosening of PS segments in interface and consequently the reduction of the amount of excimer. A reasonable mechanism was proposed to describe the molecular chain movements and phase transitions of SEBS upon heating. Moreover, the influence of temperature on the apparent activation energy of non-radiative process ( E^T ) around Tg of S block was much stronger than that around Tg of B or EB blocks.展开更多
文摘以SEBS(苯乙烯-乙烯-丁烯-苯乙烯共聚物)、SBS(苯乙烯-丁二烯-苯乙烯共聚物)、丙烯酸酯、环保型溶剂和过氧化二苯甲酰(BPO)等为原料,制备出SEBS/SBS基胶粘剂,并着重考察了SEBS掺量对胶粘剂的黏度、光学性能、电性能、力学性能及粘接性能等影响。研究结果表明:当w(SEBS)=5%~25%(相对于基体树脂总质量而言)时,胶粘剂的黏度适中,适合施工操作;当w(SEBS)=15%时,胶粘剂的接枝率、接枝效率(分别为17.11%、87.43%)相对最大,而单体转化率(为97.17%~98.36%)则变化不大;随着SEBS掺量的增加,胶粘剂的剪切强度或180°剥离强度呈先升后降态势,并且在w(SEBS)=25%或30%时相对最大(为1.87 MPa或1.73 k N/m),而且与不加SEBS体系相比分别增加了24.67%、140.28%。
文摘The temperature-induced molecular chain motions of styrenic triblock copolymers (SBC), i.e. polysty- rene-block-polybutadiene-block-polystyrene (SBS) and polystyrene-block-poly(ethylene-co-l-butene)-block-poly- styrene (SEBS), were studied by intrinsic fluorescence method. For SBS, the glass transition temperatures (Tgs) of B block and S block obtained by intrinsic fluorescence method were in good agreement with differential scanning calorimetry measurements (DSC). In the case of SEBS, an isoemission point was observed at about 310 nm at ele- vated temperatures, suggesting the slight conversion between the monomer and excimer emission. On this basis, the molecular chain motion of SEBS was monitored by both fluorescence intensity and excimer/monomer fluorescence ratio. Besides the Tgs of S block and EB blocks, a melting point (Tin) of weak crystalline in EB block was unambiguously determined by intrinsic fluorescence. Furthermore, it was found that the melting process directly led to the slight loosening of PS segments in interface and consequently the reduction of the amount of excimer. A reasonable mechanism was proposed to describe the molecular chain movements and phase transitions of SEBS upon heating. Moreover, the influence of temperature on the apparent activation energy of non-radiative process ( E^T ) around Tg of S block was much stronger than that around Tg of B or EB blocks.