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1.
用高效液相色谱跟踪2-甲基-7-亚甲基-1,4,6-三氧螺[4,4]壬烷(MMTN)与丙烯腈(AN),丙烯酸甲酯(MA)的共聚合反应。根据Lowry-Meyer共聚积分方程式,采用插值法进行数据拟合测定单体的竞聚率。对于体系MMTN(M_1)-AN(M_2),r_1=0.048;r_2=0.213;MMTN(M_1)-MA(M_2)r_1=0.025,r_2=0.764。说明两组共聚体系均有较强的交替共聚趋势。  相似文献   

2.
本文以苯为溶剂,在60±0.1℃下测定了MTMP(4-甲基丙烯酸-2,2,6,6-四甲基哌啶醇酯,M_1)与St(苯乙烯,M_2)、MVK(甲基乙烯酮,M_2)、VAc(醋酸乙烯酯,M_2)、AN(丙烯腈,M_2)的共聚物组成曲线与竞聚率(MTMP-St:r_1=0.30±0.05、r_2=0.63±0.05;MTMP-MVK:r_1=0.53±0.05、r_2=0.41±0.05;MTMP-VAc:r_1=14±0.5、r_2=0.02±0.01;MTMP-AN:r_1=13.7±0.5、r_2=0.20±0.05)。确定了MTMP的Q(0.56)和e(0.49)值。讨论了共聚物结构单元的序列分布。  相似文献   

3.
TiCl_4/MgCl_2催化丙烯/1-辛烯共聚合研究   总被引:3,自引:2,他引:3  
本文用TiCl_4/MgCl_2-Al(i-Bu)_3催化剂进行丙烯/1-辛烯共聚合,研究发现引入少量共聚单体1-辛烯时,能提高丙烯的聚合活性。30℃时,测得共聚合竟聚率为r_丙=5.63,r_辛=0.32。共聚物的结晶度和己烷不溶物含量随其1-辛烯含量的增加而迅速下降。X射线衍射及~(13)C-NMR测定结果表明,共聚物的己烷可溶部分为非结晶的无规共聚物,己烷不溶部分是具有镶嵌着半个1-辛烯单体单元的长嵌段聚丙烯链结构的结晶性共聚物。  相似文献   

4.
测定了亲水性甲基丙烯酸羟烷基酯如HEMA、MHPMA分别与AN或AAM,在60℃不同溶剂中自由基聚合反应的竞聚率。AN(M_1)-HEMA(M_2)共单体,在DMSO或DMF溶剂以AIBN或KPS-IPA引发剂条件下共聚,用Kelen-Tüds法计算的竞聚率变化不大,r_1=0.22-0.25、r_2=0.97-1.05,说明在此均相溶液共聚中,所用的溶剂及引发剂对竞聚率的影响较小,这两种单体能很好共聚。但AAM-MHPMA或AAM-HEMA共单体时,r_1与r_2值相差很大,如前者r_1=0.0433、r_2=3.98,后者r_1=0.0535、r_2=1.89,说明不易共聚,共聚物中主要是MHPMA或HEMA组分。  相似文献   

5.
用多组份改性钛系载体催化剂TiCl_4,Ti(OBu)_4/MgCl_2/Ethylbenzeate(EB)/φ_2SiCl_2/AlEt_3进行了乙烯-丙烯-1-丁烯三元共聚合的研究。考察了单体进料比、聚合温度,烷基铝浓度和催化剂浓度等条件对共聚合的影响。发现本催化剂对乙丙丁三元共聚合有极高的催化效率,聚合1h达8.6×10~4g共聚物/g-Ti。共聚合速率衰减符合动力学方程:R_s=R_s+(R_0—R_s)_e~(βs)。  相似文献   

6.
《高分子学报》2021,52(5):541-548
采用新癸酸钕(Nd(vers)_3)/氢化二异丁基铝(Al(i-Bu)_2H)/三乙基铝(AlEt_3)/乙基倍半氯化铝(EASC)体系催化丁二烯(Bd)/异戊二烯(Ip)及Bd/Ip/月桂烯(My)共聚合.所得丁戊共聚物组成与催化剂用量无关,单体的投料量与共聚物中此单体的含量几乎呈线性关系;用示差扫描量热仪(DSC)测得共聚物只有一个玻璃化转变,共聚物中Ip含量与其玻璃化转变温度(T_g)呈良好的线性关系.采用Fineman-Ross方法计算竞聚率得到r_1=1.04,r_2=1.18,Kelen-Tüdos法计算竞聚率得到r_1=1.33,r_2=1.59;r_1,r_2均接近于1,说明在此催化体系下反应可以得到无规的丁戊共聚物.利用核磁碳谱对共聚物的序列结构进行了分析和归属,采用Bernoulli模型和一级Markov模型验证共聚物的序列结构,通过比较数均序列长度,一级Markov模型计算得到的序列长度与核磁计算的实际值更接近. Bd/Ip/My三元共聚合时,所得共聚物中My单元含量随着投料比的增加而增加,其DSC曲线上只有一个玻璃化转变,T_g值随着My含量的增加而稍增加.  相似文献   

7.
研究了与偏二溴乙烯(VDBr,M_1)共聚的不同单体(M_2)——丙烯酸甲酯(MA)、甲基丙烯酸甲酯(MMA)和苯乙烯(St)的性质和共聚物的序列分布对记录材料紫外光敏性的影响。结果表明,含St的紫外光敏性最高,含MA的较差。对同一类共聚物记录材料而言,光敏性与共聚物的序列分布,主要是P_2(M_1M_2)有对应关系。本文还报道了VDBr与MA、MMA及St在55±0.2℃以偶氮二异丁腈为引发剂的自由基共聚反应竞聚率(r)分别为,VDBr-MA:r_1=0.72±0.05,r_1=0.72±0.05;VDBr-MMA:r_1=0.50±0.04,r_2=1.74±0.04;VDBr-St:r_1=0.40±0.04,r_2=1.12±0.04。  相似文献   

8.
<正> 在极性相反的单体对中,有些无需加自由基引发剂,就能进行所谓自动共聚合反应.带乙烯基的螺环原酸酯、碳酸酯和环缩醛或酮等是给电子单体,可能与接受电子的单体,如马来酸酐(Manh)进行自动共聚反应.至今,这方面研究工作报道甚少。 我们合成的2-苯基-4-亚甲基-1,3-二氧环戊烷(PMDO)能进行自由基开环聚合反应.本文研究它与受电子单体,如Manh、丙烯腈(AN)和甲基丙烯酸甲酯(MMA)的自动共聚反应.  相似文献   

9.
2—亚甲基—丁二酸酐(M_1,ITANH)和甲基丙烯酸甲酯(M_2,MMA)在四氢呋喃(THF)中以过氧化二苯甲酰(BPO)作引发剂进行自由基共聚合。由作图法衣得这两种单体在66℃的共聚竞聚率:表明它们趋于嵌均共聚。用粘度法和GPC测量了共聚物的分子量和分子量分布。共聚物在温和的条件下进行部分水解,得到一带有短的羧基侧链的聚电解质[11]。将[11]与无机盐LiClO_4混合后测得电导率δ-2.8272×10~(-4)S·cm~(-1),表明它具有较好的离子导电性。  相似文献   

10.
红外光谱法测定St—BMA的竞聚率   总被引:2,自引:0,他引:2  
对于共聚合反应中同一对单体的竞聚率,由于采用的实验方法、计算方法不同,可能有几对、甚至上百对不同的数据。在实际生产中已逐渐趋向于在较高温度下进行共聚合,而文献的竞聚率一般均在较低温度下获得,因此缺乏实用意义。本文用FTIR方法测定苯乙烯(St)-甲基丙烯酸正丁酯(BMA)共聚竞聚率参数r_1和r_2,讨论了温度的影响。  相似文献   

11.
在水热条件下,合成了1个新的双核锌配合物[(ZnCl2)(PyBIm)]2(PyBIm=2-(4-pyridyl)benzimidazole)。该配合物为单斜晶系,P21/n空间群,晶胞参数a=0.774 51(4) nm,b=1.252 49(5) nm,c=1.315 96(7) nm,β=100.294(3)°,V=1.256 0(1) nm3,Z=2。结构分析表明,Zn被2个Cl原子和来自PyBIm配体的2个N原子配位,形成了1个变形四面体结构。在该配合物中,Zn…Zn距离为 0.709 4(5) nm,结构中存在π…π堆积和氢键作用。  相似文献   

12.
The radical polymerizability of vinylpyridines in the presence of cobaltous chloride was studied in DMF solution, and the results were correlated with the spectroscopic data obtained for methanol solution. In general, the behavior of vinylpyridine complexed with cobaltous chloride is qualitatively the same as that of zinc complexes reported previously. The rates of polymerization were enhanced by the addition of cobaltous chloride when 4-vinylpyridine(4-VP) or 2-methyl-5-vinylpyridine(MVP) was the monomer, whereas the polymerization of 2-vinylpyridine(2-VP) was retarded by cobaltous chloride. The monomer reactivity of all the vinylpyridines was also enhanced by complex formation as studied by copolymerization with styrene. The enhancement of reactivity of 4-VP complexed with cobaltous chloride is somewhat smaller than that of the corresponding zinc complex.  相似文献   

13.
The first report on the preparation, polymerization, and copolymerization of a nitrosyl-containing vinylcyclopentadienylmetal monomer, (η5-C5H4CHCH2)-Cr(CO)2NO, is described. (η5-Vinylcyclopentadienyl)-dicarbonylnitrosylchromium (A) was prepared in good yield by the acylation of η5-cyclopentadienyl-carbonylnitrosylchromium followed by sodium borohydride reduction of the keto function and acid-catalyzed dehydration. Monomer A homopolymerizes and copolymerizes with styrene, N-vinylpyrrolidone, and vinyl cymantrene in the presence of azo initiators. Reactivity ratios in the copolymerization of A with styrene were r1 = 0.30 and r2 = 0.82 from which the value of e for A was found to be ?1.98. Thus, A is an exceptionally electron-rich monomer.  相似文献   

14.
The title complex [NH_3CH_2CH(NH_2)CH_3]_2 [M(Ⅵ)O_2(OC_6H_4O)_2](M= Mo_(0.6)W_(0.4))was synthesized via a simple solution-phase chemical route.The determination of single crystal X-ray diffraction revealed that the title compound is crystallized in a monoclinic system with P2(1)/n space group,a=1.0913(10)nm,b=1.0442(10)nm,c=1.8842(19)nm,α=90°,β=96.530(17)°,γ=90°,Z=4,and V=2.133(4)nm3.The mononuclear anionic unit [M(Ⅵ)O2(OC6H4O)2]2-displays chiral pseudo-octahedral [MO_6] coordination geometry and is linked by chiral cations via hydrogen bond and π…π stacking interaction.The transmission electron microscopy images show that the title complex is comprised of nano-particles with diameters ranging from 20 to 50 nm.The NMR study shows the 1H downfield chemical shifts of [NH_3CHaHbCH(NH_2)CH_3] cations in the title complex when it is mixed with adenosine-triphosphate(ATP),and the chemical shift difference between Ha and Hb is increased greatly,and most of the catecholate ligands dissociate from the central metal atoms.The DNA cleavage activity experiment reveals that DNA cleavage promoted by the title complex is lower than that by Na_2MoO_4 which possesses antitumor pro-perty,but higher than that by Na_2WO_4.  相似文献   

15.
采用自由基引发剂对甲基丙烯酸三丁基锡酯和丙烯酸酯进行共聚合 ,其竞聚率用YBR法解出共聚方程的微分式而求得。甲基丙烯酸三丁基锡酯 (M1 )和丙烯酸甲酯 (M2 )、丙烯酸乙酯 (M2 )、丙烯酸丁酯 (M2 )共聚反应的竞聚率分别为r1 =1 .0 1± 0 .0 6, r2 =0 .2 9± 0 .0 3; r1 =1 .0 7± 0 .0 5 ,r2 =0 .38± 0 .0 3; r1 =1 .1 1± 0 .0 5 , r2 =0 .45± 0 .0 3; 而所得到的甲基丙烯酸三丁基锡酯的Q、e值是它对各个单体的所有Q、e值的平均值 ,其Q =0 .5 7,e=- 0 .39  相似文献   

16.
The coordinating properties of the trifluoromethyl elemental compounds Me2PP(CF3)2 and Me2AsP(CF3)2 have been studied by the synthesis and spectroscopic investigations (IR, NMR, MS) of their complexes cis-M(CO)4L2 (A), [(CO)4ML]2 (B) and [(CO)5M]2L (C) (M = Cr, Mo, W). Complexes of type A with L = Me2PP(CF3)2 are obtained in good yield by reaction with M(CO)4NBD (NBD = norbornadiene), whereas with L = Me2AsP(CF3)2 the homobinuclear compounds B are formed. The attempt to prepare the cis-M(CO)4[Me2AsP(CF3)2]2 complexes by treating M(CO)4(Me2AsH)2 with P2(CF3)4 is successful only for M = W. Binuclear compounds of type B or C, in general, can be prepared by stepwise reaction of the ligands with either M(CO)4NBD or M(CO)5THF.  相似文献   

17.
<正>近年来,铅的配位聚合物以其丰富的结构与在离子交换和光学等领域中的应用前景[1-3]而引起了广泛关注。由于铅的原子半径较大,可以形成较高的配位数[4-6];另外,二价铅的6s轨道上有一对孤对  相似文献   

18.
The initiation mechanism of the copolymerization of 2-vinylnaphthalene with maleic anhydride was studied under irradiation of 365 nm. The excited complex was formed from (1) the local excitation of 2-vinylnaphthalene followed by the charge-transfer interaction with maleic anhydride and (2) the excitation of the ground state charge-transfer complex, and then it collapsed to 1,4-tetramethylene biradical for initiation. A1: 1 alternating copolymer was formed in different monomer feeds. Addition of benzophenone could greatly enhance the rate of copolymerization through energy-transfer mechanism.  相似文献   

19.
Effects of substituents on cyclopentadienyl group for homopolymerization of ethylene, 1-hexene, and for ethylene/1-hexene copolymerization using a series of nonbridged (cyclopentadienyl)(ketimide)titanium complexes of the type, Cp′TiCl2(N=CtBu2) [Cp′ = Cp (1), tBuC5H4 (2), C5Me5 (Cp*, 3), and indenyl (4)] have been explored in the presence of methylaluminoxane (MAO) cocatalyst. Complexes 1–3 showed the similar catalytic activities for ethylene polymerization although the activity by 4 was somewhat low, whereas the activity for 1-hexene polymerization increased in the order 1 > 4 2 > 3. These complexes showed significant activities for ethylene/1-hexene copolymerization affording high molecular weight poly(ethylene-co-1-hexene)s with unimodal molecular weight distributions, and the activity increased in the order: 4 > 1 2, 3. The rErH values in the polymerization by 1–3 at 40 °C were 0.35–0.52 which clearly indicate that the 1-hexene incorporation in the copolymerization did not proceed in a random manner. The rE values by 1–3 were 6.0–6.4 and the values were independent upon the cyclopentadienyl fragment employed; the rE values by 4 at 40 °C were 10.2–10.9 which were close to those by ansa-metallocene complex catalysts. These values were influenced by the polymerization temperature, and the 1-hexene incorporation by 1–4 became inefficient at higher temperature, although the observed activities especially by 1, 4 were highly remarkable.  相似文献   

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