如何看懂DSC曲线公开课获奖课件.pptx

单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,示差扫描量热法,(,Differential Scanning Calorimeter，DSC),国际原则ISO 11357-1：,DSC是测量输入到试样和参比物热流量差或功率差与温度或时间关系,第1页,DSC与DTA测定原理不一样样,DSC是在控制温度变化状况下，以温度（或时间）为横坐标，以样品与参比物间温差为零所需供应热量为纵坐标所得扫描曲线。,DTA是测量T-T 关系，而DSC是保持T=0，测定H-T 关系。两者最大差异是DTA只能定性或半定量，而DSC成果可用于定量分析。,第2页,第3页,第4页,第5页,第6页,示差扫描量热测定期记录热谱图称之为DSC曲线，其纵坐标是试样与参比物功率差dH/dt，也称作热流率，单位为毫瓦（mW），横坐标为温度（T）或时间（t）。一般在DSC热谱图中，吸热(endothermic)效应用凸起峰值来表征(热焓增长)，放热(exothermic)效应用反向峰值表征(热焓减少)。,第7页,曲线,玻璃化转变,结晶,基线,放热行为,（固化，氧化，反应，交联）,熔融,固固,一级转变,分解气化,DTA,曲线,吸热,放热,T,(),dH/dt(mW),T,g,T,c,T,m,T,d,DSC,第8页,4.1 玻璃化转变温度测定,d,Q/dt,d,Q/dt,温度,温度,T,g,T,g,1/2,从DSC曲线上确定Tg措施,第9页,T,g,体积,温度,玻璃化转变温度前后体积变化率不一样样,第10页,体积收缩过程是一级过程：,v,为体积松弛时间，即过剩自由体积排出,l/e,时间。,聚合物体内过剩自由体积越多，收缩越快。,玻璃化转变动力学本质,第11页,聚苯乙烯：100,C,松弛时间约为0.01秒，95,C,时约为1秒，77,C,时约为一年。以1,C/,min,降温速度测定,PS,玻璃化温度约为90,C,，即松弛时间为1-5,min,温度范围。,100,95,91,90,89,88,85,7977,0.01秒,1秒,40秒,2分钟,5分钟,18分钟,5小时,60小时,1年,温度(,C,),v,第12页,Heat Flux,Endothermic,Exothermic,Glass,Liquid,T,g,T,g,10 50 90,Temperature,C,热焓松弛对,T,g,测定影响,20C/min,上曲线：无预处理,下曲线：150C保温1min,迅速冷却至室温(320C/min),样品：某线形,环氧树脂,第13页,10 50 90,Temperature,C,(320),(40),(10),(2.5),(0.62),51,51,51,52,54,样品冷却速率对,T,g,测定影响,150C预热后以()C/min冷却速率降到Tg如下再测定,第14页,10 50 90,Temperature,C,0,2,25,53,56,51,样品放置时间对,T,g,时间影响,从,150C,以,320C/min,降到室温后放置 天再测定,第15页,-样品用量1015 mg,-以20C/min加热至发生热焓松弛以上温度,-以最迅速率将温度降到预估Tg如下50C,再以20C/min加热测定Tg,对比测定前后样品重量，如发既有失重则反复以上过程,T,g,测定推荐程序,第16页,研究实例：轮胎橡胶,T,g,测定,轮胎橡胶Tg重要性：,Tg值高(约-40C)，抓着性高，但滚动阻力大，耐磨差，耐低温性差,Tg低(约-90C)，滚动阻力小，耐磨高，耐低温性高，但抓着性差,因此轮胎橡胶都是不一样样胶共混物,第17页,ESBR,SSBR,BR,丁二烯橡胶,-,100 -20,C,NR,天然橡胶,IR,异戊二烯橡胶,常用轮胎胶,丁苯橡胶,-100,100,C,第18页,丁二烯橡胶是三种单元共聚物，即顺式、反式、乙烯基。,BR T,g,可由,Gordon-Taylor,公式计算：,W,i,A,i,(T,g,-T,g,i,)=0,其中,W,i,为单元,i,重量分数,，,T,g,为共聚物玻璃化温度，,T,g,i,为单元,i,均聚物玻璃化温度,Ai是一种常数，一般取体积膨胀系数,第19页,W,i,A,i,T,g,-T,g i,)=0,假定有三个组分：,W,1,A,1,(T,g,-T,g1,)+W,2,A,2,(T,g,-T,g2,)+W,3,A,3,(T,g,-T,g3,)=0,T,g,(W,1,A,1,+W,2,A,2,+W,3,A,3,),=W,1,A,1,T,g1,+W,2,A,2,T,g2,+W,3,A,3,T,g3,第20页,W为重量分数，下标c,t,v 分别代表顺-l,4,反-l,4 和乙烯基构造,Tg,c,t,v 分别代表三种构造均聚物Tg,Kn =(n+l)/1 为体积膨胀系数之比,聚丁二烯,T,g,可用下式计算,第21页,T,g,c,=164 K(-109,C),T,g,t179 K(-94,C)K,1,=0.75,T,g,v,=257 K(-16,C)K,2,=0.50,W,c,+W,t,+W,v,=1.0,误差,0.5,C,第22页,在此基础上可扩充为计算,SSBR,公式,T,g,s,=,聚苯乙烯,T,g,，378 K,W,s,=,苯乙烯单元重量分数,K,3,0.6,第23页,()%,wt styrene,(on total polymer),DSC T,g,C,1.2,BR fraction(of the total BR part),20,10,0,10,20,30,40,50,60,70,80,90,100,0.00 0.20 0.40 0.60 0.80 1.00,(70),(60),(50),(40),(30),(20),(10),(0),1,2构造与S单元对SSBR Tg影响,第24页,Temperature(,C),Heat Flow(W/g),0.30,0.25,0.20,0.15,0.10,0.05,0.00,120 110 100 90 80 70 60 50 40,internal mixer(50,C,),prepared sample,sample prepared from,cyclohexane solution,Tg effects of SSBR/BR(75/25)blends两者不相容，两个Tg,第25页,sample prepared from,a toluene solution,internal mixer(50,C,),prepared sample,Thermally treated,Temperature(,C),Heat Flow(W/g),0.24,0.22,0.20,0.18,0.16,0.14,0.12,0.10,0.08,0.06,0.04,0.02,0.00,90 80 70 60 50 40 30,低vinyl(8.5%wt)与高vinyl(40.5%wt)SSBR 完全相容，只有一种Tg，但可以从峰加宽与峰位移判断是共混物。,第26页,T,g,-value SSBR blends,calculated,measured,high vinyl content SSBR weight fraction,40,45,50,55,60,65,70,75,80,0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0,计算值与测定值比较,第27页,0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0,40,45,50,55,60,65,70,75,80,T,g,of oil-extended SSBR and ESBR systems,measured values,T,g,oil-extended rubber,C,SSBR,aromatic oil,ESBR,SSBR,naphtenic oil,oil wt fraction,充油体系,常用芳香油Tg 232K(-41C)或萘油Tg208 K。芳香油Tg高于SBR，使Tg升高，萘油使Tg减少。,第28页,4.2 熔融与结晶,表征熔融三个参数：,T,m,:,吸热峰峰值,H,f,：,吸热峰面积,T,e,：,熔融完全温度,表征结晶两个参数：,T,c,：,放热峰峰值,H,c,：,放热峰面积,exo,1.0,0.8,0.6,0.4,0.2,0.0,100 150 200 250 300 350,Temperature,C,T,m,H,f,T,e,T,c,H,c,第29页,4.2,mg,3.1mg,5.2mg,8.1mg,12.4mg,6.0,5.5,5.0,4.5,4.0,3.5,3.0,2.5,2.0,1.5,1.0,0.5,0.0,6.0,5.5,5.0,4.5,4.0,3.5,3.0,2.5,2.0,1.5,1.0,0.5,0.0,200 210 220 230 240 250 260 270,Temperature(,C),Heat Flow(W/g),样品量与,T,m,值关系,第30页,假如熔融不完全，残存晶粒会导致“自成核”，使结晶温度升高。从表可以看出，PP样品至少应在210 C熔融。,1.,heating,T,max,C,2.,cooling,3.,heating,T,m1,C,H,f1,J/g,T,c,C,H,c,J/g,T,m2,C,H,f2,J/g,162.5,100,230,108.6,101,160.9,95,162.1,102,220,108.7,99,160.5,96,162.5,97,210,108.7,96,161.0,95,162.5,99,200,109.2,102,161.0,90,162.4,88,190,109.3,98,161.0,95,162.2,99,180,110.0,98,161.2,98,第31页,1.,heating,T,max,.,C,2.,cooling,3heating,T,m1,C,H,f1,J/g,T,c,C,H,c,J/g,T,m2,C,H,f2,J/g,162.5,100,230,108.6,101,160,.9,95,162.1,102,220,108.7,99,160,.5,96,162.5,97,210,108.7,96,161,.0,95,162.5,99,200,109.2,102,161,.0,90,162.4,88,190,109.3,98,161.0,95,162.2,99,180,110.0,98,161.2,98,总结出：Tm1:162.4C 0.2C Hf1:97 J/g 5 J/g,Hf 误差大是由于取基线导致。,Hc:99 J/g 2 J/g Tm2:160.9C 0.2C Hf2:95 J/g 3 J/g,后三个值反复性提高是由于样品熔融后与容器充足接触所致。,第32页,结晶与熔融点必须反复循环加热冷却，才能得到可反复数据。,Tm 与 Tc 测定反复性在3C左右,这一误差比Tg测定要高,第33页,PP,结晶与熔融,无规,PP,T,g,=,-21,C,间规,PP,(,结晶度,25%,wt.)T,m,=,133,C,等规,PP,(,结晶度,50%wt.)T,m,=160,C,i-PP,中最常见是,晶格,单斜，,T,m,=,160,C.,压力下结晶会产生,晶格，六方，,T,m,=,152,C,第34页,i-PP 结晶温度为110C，过冷度为50C。模塑效率太低。,成核剂可缩短模塑时间，减小球晶尺寸，同步提高光学/力学性质,4-biphenyl carboxylic acid 与 2-naphtoic acid 可将Tc从110C提高到130C.,PP,成核剂,第35页,Talc%wt.,Carbon black%wt.,Total add.,%wt.,T,c,C,H,c,J/g,T,m2,C,0.00,0.00,0.00,110,91,158,0.05,0.00,0.05,115,97,161,0.19,0.00,0.19,118,95,161,0.00,0.47,0.47,120,91162,0.53,0.00,0.53,118,97,161,0.38,0.59,0.97,124,95,163,0.35,0.70,1.05,125,96,163,0.00,1.37,1.37,125,97,163,0.76,0.85,1.61,125,96,164,9.57,1.02,10.59,114,95,160,滑石粉和碳黑作成核剂效果,第36页,PP T,m2,-value/T,c,-value,Additives:talc/carbon black,PP T,c,-value,C,128,126,124,122,120,118,116,114,112,110,108,0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8,Additive content,%wt,PP Tm2-value,C,T,c,C,166,165,164,163,162,161,160,159,158,157,156,108 112 116 120 124 128,PP,成核剂,效果图示,第37页,成核效率,T,ca,:,加成核剂后结晶温度,T,c1,:,未加成核剂结晶温度,T,c2,:,体系自成核最高结晶温度,第38页,加炭黑0.70,wt%,滑石粉0.35,wt%PP:T,c,=125,C,加滑石粉0.53,wt%PP:T,c,=118,C,第39页,退火对熔点与焓值影响,样品：,HH-SB-35,等规度：96%,M,w,=300,000 M,w,/M,n,5.0,4mg,样品加热到退火温度,T(a),保持时间,t(a),冷却到,20,C,，再加热到,220,C,加热/冷却速率均为,20,C/min,背景：PP平衡熔点为185或208C。结晶温度仅为110130C左右。这样大差异表明结晶与热历史关系亲密。,第40页,Temperature(,C),Heat Flow(W/g),7.0,6.5,6.0,5.5,5.0,4.5,4.0,3.5,3.0,2.5,2.0,1.5,1.0,0.5,130 140 150 160 170 180 190,Annealed at,163,C during:,30min,15min,5min,退火时间影响,该图表明火时间应为,30min,第41页,Temperature(,C),Heat Flow(W/g),7.0,6.5,6.0,5.5,5.0,4.5,4.0,3.5,3.0,2.5,2.0,1.5,1.0,0.5,130 140 150 160 170 180 190,163,C,164 C,165 C,30 min,annealed at:,退火温度影响,第42页,T(a),C,T,c,C,T,m,C,H,f,J/g,T,m,C,H,f,J/g,146,161.0,76,150,163.4,81,152,165.1,79,156,168.7,78,159,172.0,91,161,174.4,109,162,175.8,110,163,175.8,107,164,141.4,178.3,31,161.3,69,164.5,140.8,178.7,12,163.5,81,165,140.9,179.2,11,164.2,89,166,138.9,179.2,2,164.2,97,166.5,138.3,179.5,1,164.6,99,167,135.8,163.6,100,略有增长,Tm随T(a)增长,Hf经历极大值,表明结晶最完善,曲线双峰,T,m,呈最大值,H,f,降为零，,H,f,上升，T,m,恒定。,H,f,T,m,下降,第43页,Annealing temperature Ta,C,Tm-/Hf值随退火温度变化,180,178,176,174,172,170,168,166,164,162,160,180,160,140,120,100,80,60,40,20,0,145 151 157 163 169 175,T,m,0.993;斜率从13.5 phr 0.49 增长到24 phr 0.55,13.5,17,20.5,第67页,Time/curing agent concentration relation necessary to reach a T,g,-value of the,cured product of at least 100,C,Cure time at 180 C,s,(Cure temperature 180 C),Epoxy resin based powder coating system,curing agent concentration,phr,1000,200,10 12 14 16 18 20 22 24 26,T,g,高于,100,C,所需时间,第68页,聚合反应动力学,含不一样样长度脂肪链酰亚胺聚合,由亚甲基丁二酸酐与脂肪二胺通式为H2N-(CH2)n-NH2，其中n=6,8,10和12出发，合成一系列构造类似含脂肪链酰亚胺，运用DSC研究具有如下构造此类甲基顺丁烯酰亚胺聚合动力学。,C,O,N,(CH,2,),n,C,O,C,HC,H,3,C,C,CH,2,CH,2,O,O,N,C,C,第69页,甲基顺丁烯酰亚胺(,n=6)DSC,升温曲线,总面积,A:,总放热,a:,时刻,t,放热之和,已反应分数,A-a:,时刻,t,未反应分数,dQ/dt:,反应速率,放热,dQ/dt,吸热,340,T 440,a,A-a,T/K,熔融吸热,(72,C),第70页,可由1条升温DSC曲线求得在不一样样温度处k值，于是由Arrhenius图(lgk1/T)斜率可求得聚合反应活化能。试验成果显示Arrhenius图线性良好，反应符合1级反应。随柔顺亚甲基链段长度增长(甲基数由6增长至12)，聚合活化能从75kJ/mol降至30kJ/mol。,如假定该反应为1级反应，便可直接写出速率方程：,dQ/dt=k(A-a),k=(dQ/dt)/(A-a),T,a,A-a,dQ/dt,第71页,P(S-PFS):,苯乙烯-对氟苯乙烯共聚物,PPO:,聚苯醚,PFS,摩尔含量为8-56%时，体系相容。高于56%后，发生相分离。,P(S-PFS),和,PPO,共聚混合物,DSC,曲线,PFS,摩尔含量,8%,16%,25%,36%,46%,49%,56%,67%,78%,热流量,107 227,T(,C,),4.4 相容性研究,第72页,S.C.Lee et al.,Polymer,1997,38,4831.,.,The arrow indicates the position of T,g,PEN/PET(50/50)blend The time indicates the reaction time at 280,C,Temperature,C,Temperature,C,3min,5min,7min,9min,11min,13min,15min,20min,180min,PEN/PET(w/w),Exothermic,100/0,70/30,50/50,30/70,0/100,0 50 100 150 200 250 300,0 50 100 150 200 250 300,Exothermic,PEN、PET共混与酯互换过程,第73页,Change of the glass transition behavior with the reaction time at 280,C for the PEN/PET(50/50)blend,130,120,110,100,90,80,70,EN-rich phase,ET-rich phase,0 10 20 30 40 50 60 80,Reaction Time(min),T,g,(,C),第74页,140,130,120,110,100,90,80,70,0 20 40 60 80 100,T,g,(,C),EN Content(wt%),EN/ET copolymers prepared by heat treating of PEN/PET blends at 280,C for 180min.,T,g,=w,1,T,g1,+w,2,T,g2,第75页,聚苯乙烯/离聚物共混,聚苯乙烯：,M,n,=1.06,1,0,5,，M,w,/M,n,=1.93,聚苯乙烯磺酸锌盐：,增容剂：苯乙烯/乙烯基吡啶嵌段共聚物,Compatibilization of blends of polystyrene and zinc salt of sulfonated polystyrene by poly(styrene-,b,-4-vinylpyridine)diblock copolymer,Polymer 40(1999)22392247,第76页,扫描电镜,液氮折断，THF清除PS相,(,a)0 (b)2.0 (c)4.1 (d)7.3,PS/Zn-SPS 70/30(wt/wt)+P(S-,b,-4VPy),括号中数字为增容 剂量,即,P(S-,b,-4VPy),重量/两种,PS,总重量,第77页,低于此配比时一种Tg，,相容,高于此配比时两个Tg，,不相容,Zn-SPS/P4VPy,相容性,40 60 80 100 120 140 160 180,Temperature(,C),ENDO,88.4/11.6,93.2/6.8,96.6/3.4,0/100,锌离子与吡啶氮化学计量比为93.2/6.8(,wt/wt),Zn-SPS/P4VPy,第78页,neat PS：100.2,C,neat Zn-SPS：122.2,C,70/30 blends+P(S-,b,-4VPy),(c)0：,2,T,g,(d)2.0 wt%：,2,T,g,(e)4.1 wt%：,2,T,g,(f)7.3 wt%：,3,T,g,40 60 80 100 120 140 160 180,a,b,c,d,e,f,Temperature(,C),ENDO,Zn-SPS,为聚苯乙烯磺酸锌盐,共混体系相容 性,第79页,Viscoelastic and thermal properties of collagen/poly(vinyl alcohol)blends,Biomoteriols 16(1995)785-792,聚乙烯醇与胶原蛋白合金,背景：生物材料力学性能差，合成材料生物相容性差，两者结合后与否相容？,第80页,PVA/,胶原合金,DSC,一次扫描有严重热焓松弛，二次扫描消失,峰为胶原denaturation(变性)，两者Tg靠近，无法判断与否相容,一次扫描 二次扫描,图中数字为胶原,wt%,干,PVAT,g,=80,C，T,m227,C,含水,PVAT,g,=42,C,0 40 80 120,endo exdo,100,0.1,W/g,0 40 80 120,endo exdo,0.1,W/g,T(,C,),T(,C,),50,30,0,70,100,70,50,30,0,第81页,PVA/,明胶合金,DSC,一次扫描 二次扫描,清晰地出现两个Tg，且不随构成变化，表明两者不相容,0 40 80 120,endo exdo,100,0.1,W/g,T(,C,),0 40 80 120,endo exdo,0.1,W/g,T(,C,),0,30,50,70,100,70,50,30,0,第82页,从PVA/明胶合金DSC谱图测量吸热幅度与构成呈线性关系，也表明不相容,0.8,0.6,0.4,0.2,0,0.8,0.6,0.4,0.2,0,0 0.5 1,明胶重量分数,W,C,p,(J/g,C,),低温转变(,PVA),高温转变(明胶),第83页,4.5 用,DSC,测溶度参数,先将被测物置于封闭容器中10min，抵达平衡后打开容器盖，蒸发液体，测定焓值。,第84页,A,B,A:DSC cell base,B:polycarbonater cell cover,Stopping block,Spring loaded,magnets holder,magnets,mild steel lid,rubber O-ring,仪器改造示意图,第85页,Sample cuphole diam.,Average,Hvap.25 measured,kJ/mol,Correction factor,0.5,mm.,38.4,0.4,1.14,3.0,mm.,39.5,0.2,1.11,4.0,mm.,39.0,0.2,1.13,仪器用水校正：水焓值：43.9,kJ/mol.,第86页,MCAL/SEC,5.0,2.5,0.0,Time(min),1 2 3 4 5 6 7 8,A,B,C,DSC curve of the vaporization of ethyl propionate,A,点：开盖,B,点：完全蒸发,C：,积分基线,第87页,solvent,boiling,tempera,ture,C,Hvap.25,exper.,kJ/mol,Hvap.25,literat.,kJ/mol,+/-,%,acetone,57,30.8,30.5,+1.0,methanol,65,38.0,37.4,+1.4,ethanol,79,42.1,42.3,-0.5,4-,methyl-2,pentanone,116,40.6,40.6,0.0,2-,heptanone,147,47.3,47.2,+0.2,n-dodecane,214,62.6,61.3,+2.1,测试成果与文献值,第88页,MCAL/SEC,0.30,0.15,0.00,Time(min),0 6 12 18 24 30 36 42 48 54 60,DSC curve of the vaporization of n-dodecane at 25,C,endo,第89页,56,53,50,47,44,41,38,35,32,29,70 80 90 100 110 120 130 140 150,n-acetates,branched acetate,n-propionates,branched propionate,Molecular weight,Heat of vaporizatrion at 25,C,kJ/mol,第90页,完,第91页,PEEK 和PEI相容性，第一次（红）和第二次加热（绿），20K/min。第一次时，PEEKTg为147C，PEITg为217C。第二次时，合并为一种Tg:172C。在224C时PEEK发生冷结晶。,Glass transition(2),Onset:155.8,C,Midpt:172.1,C,Inflpt:166.8,C,Endpt:188.4,C,Del cp:0.19 J/(g,K),exo,DSC/mW/mg,1.0,0.8,0.6,0.4,0.2,0.0,338.4,C(2),29.07 J/g,340.9,C(1),29.16 J/g,-20.66 J/g(1),223.9,C,100 150 200 250 300 350,Temperature,C,214.5,C(1),第92页,