EVA/EPDM/IR/IR共混发泡材料的性能研究

研究了乙烯醋酸乙烯酯共聚物（ＥＶＡ）／ＥＰＤＭ／ＩＲ三元共混和ＥＶＡ／ＥＰＤＭ／ＩＲ／ＩＲ四元共混发泡材料的性能。在ＥＶＡ中混入ＥＰＤＭ可使发泡材料的拉伸强度、撕裂强度和粘合强度提高,而收缩率和压缩永久变形降低;在ＥＶＡ中混入ＩＲ除具备混入ＥＰＤＭ同样的优点外,还可提高发泡材料的柔性;ＩＲ的混入可改善发泡材料二次热压成型制品的表面清晰度。     

EVA/EPDM/IR/IR共混发泡材料的研制与应用

进行了ＥＶＡ／ＥＰＤＭ／ＩＲ三元共混和ＥＶＡ／ＥＰＤＭ／ＩＲ／ＩＲ四元共混发泡材料的研制,经物性对比表明：共混发泡材料的物性较非共混发泡普遍提高。ＥＰＤＭ的混入可以增加发泡材料的拉伸强度和撕裂强度,同时降低收缩率和永久压缩变形;ＩＲ的混入除具备ＥＰＤＭ的优点外尚对提高发泡材料的柔软度有帮助;ＩＲ的混入仅改善发泡材料二次热压成型制品表面的清晰度。     

EVA／EPDM／IR／IIR共混发泡材料的研制与应用

进行了ＥＶＡ／ＥＰＤＭ／ＩＲ三元共混和ＥＶＡ／ＥＰＤＭ／ＩＲ／ＩＩＲ四元共混发泡材料的研制,经物性对比表明：共混发泡材料的物性较非共混发泡普遍提高。ＥＰＤＭ的混入可以增加发泡材料的拉伸强度和撕裂强度,同时降低收缩率和永久压缩变形;ＩＩＲ的混入除具备ＥＰＤＭ的优点外尚对提高发泡材料的柔软度有帮助;ＩＲ的混入仅改善发泡材料二次热压成型制品表面的清晰度。     

EVA/EPDM/IR共混发泡材料的研制与应用

报道了ＥＶＡ／ＥＰＤＭ／ＩＲ共混发泡材料的制作方法,二次成型的工艺条件。比较了共混发泡和非共混发泡物理性能的差别和共混发泡材料的用途。     

反应挤了HDPE／PET共混合金结构与性能研究

采用ＤＳＣ、ＷＡＸＤ、ＳＥＭ及ＴＧＡ等方法研究了ＨＤＰＥ／ＰＥＴ共混合金在增溶剂Ｅ／ＶＡＣ或Ｅ／ＡＡ作用下的结晶性、形态结构及热稳定性。结果表明，Ｅ／ＶＡＣ或Ｅ／ＡＡ的加入，使ＨＤＰＥ／ＰＥＴ体系中ＨＤＰＥ组分的熔融热焓降低，结晶度下降，但熔融峰位置和晶胞基本保持不变；从ＳＥＭ照片可以观察到Ｅ／ＶＡＣ、Ｅ／ＡＡ对共混体系具有一定的增容作用，Ｅ／ＡＡ和效果优于Ｅ／ＶＡＣ；共混体系的热稳定性随Ｅ／ＶＡ     

CPE增容PVC／EPDM共混体系力学性能研究

以聚氯乙烯（ＰＶＣ）为主体材料，新型三元乙丙橡胶（ＥＰＤＭ）为改性剂，氯化聚乙烯（ＣＰＥ）为增容剂进行共混，来改善ＰＶＣ的抗冲击性能。实验结果表明，ＰＶＣ和一定量的ＣＰＥ、ＥＰＤＭ共混改性后，共混体系的冲击强度大幅度提高，ＰＶＣ／ＣＰＥ／ＥＰＤＭ在１００／５／１０（Ｗ／Ｗ）时，冲击强度上升值最大，可达４３．７ｋＪ／ｍ＾２，拉伸断裂强度提高近３０％。     

FPE和PVC的相互作用及其对PVC/CPE/FPE合金性能和形态结构的影响

用ＦＴＩＲ光谱证实了ＰＶＣ与ＰＥ８ＤＢＭ（简称ＦＰＥ）之间存在着氢键和偶极偶极的作用,其中以氢键作用为主。测定了ＰＶＣ／ＣＰＥ／ＰＥ和ＰＶＣ／ＣＰＥ／ＦＰＥ合金的力学性能,用ＤＳＣ、相衬显微镜及ＳＥＭ表征了这两个体系的微观形态结构,研究了共混物中异种分子间的相互作用对合金性能与形态结构的影响     

高聚合度聚氯乙烯共混改性研究 Ⅱ.高聚合度聚氯乙烯/EPDM共混体系

研究了共混方法,共混温度,共混时间,共混对比高聚合度聚氯乙烯（ＨＰＶＣ）／ＥＰＤＭ共混物结构和性能的影响,结果表明,采用一阶共混法可获最佳共混效果,共混温度宜为１７０～１７５℃,ＨＰＶＣ／ＥＰＤＭ共混体系是热力学不相容体系,其较好的界面相容剂为氯乙烯和聚乙烯接枝马来酸酐,用量以９份为宜（对于共混比为３０／７０）的体系）,Ｋｒａｕｓ方程可以较好地表征ＨＰＶＣ／ＥＰＤＭ共混体系的界面作用强度。     

EVA／EPDM／PVC三元塑料合金软质泡沫体的生产及其应用

采用物理共混及化学交联模压发泡工艺生产乙烯－醋酸乙烯酯共聚物（ＥＶＡ）／三元乙丙橡胶（ＥＰＤＭ）／聚氯乙烯（ＰＶＣ）三元塑料合金软质泡沫体。讨论了该体系的相容性、共交联与发泡的适配等问题，介绍了其复合衬垫的制造工艺及特点，生产实践证明，该材料的复合衬垫可完全替代国外同类产品。     

高聚合度聚氯乙烯共混改性研究 Ⅱ.高聚合度聚氯乙烯/EPDM共混体系

研究了共混方法、共混温度、共混时间、共混比对高聚合度聚氯乙烯（ＨＰＶＣ）／ＥＰＤＭ共混物结构和性能的影响。结果表明,采用一阶共混法可获得最佳共混效果,共混温度宜为１７０～１７５℃,ＨＰＶＣ／ＥＰＤＭ共混体系是热力学不相容体系,其较好的界面相容剂为氯化聚乙烯和聚乙烯接枝马来酸酐,用量以９份为宜（对于共混比为３０／７０的体系）。Ｋｒａｕｓ方程可以较好地表征ＨＰＶＣ／ＥＰＤＭ共混体系的界面作用强度。     

Wet Milling of Fe/Al/Al2O3 and Fe2O3/Al/Al2O3 Powder Mixtures

Wet milling of Al₂O₃-aluminide alloy (3A) precursor powders in acetone has been investigated by milling Fe/Al/Al₂O₃ and Fe₂O₃/Al/Al₂O₃ powder mixtures. The influence of the milling process on the physical and chemical properties of the milled powders has been studied. Particle refinement and homogenization were found not to play a dominant role, whereas plastic deformation of the metal particles leads to the formation of dislocations and a highly disarranged polycrystalline structure. Although no chemical reactions among the powder components in Fe₂O₃/Al/Al₂O₃ powder mixtures were observed, the formation of a nanocrystalline, ordered intermetallic FeAl phase in Fe/Al/Al₂O₃ powder mixtures caused by mechanical alloying was detected. Chemical reactions of Fe and Al particle surfaces with the atmosphere and the milling media lead to the formation of highly porous hydroxides on the particle surfaces. Hence the specific surface area of the powders increases, while the powder density decreases during milling. The fraction of Fe oxidized during milling was determined to be 0.13. The fraction of Al oxidized during milling strongly depends on the metal content of the powder mixture. It ranges between 0.4 and 0.8.     

Preparation and properties of poly(Nε,Nε-dicarboxymethyl-l-lysine)

A new ampholytic homopolypeptide, $\text{poly}\text{(N}{}^{\mathrm{\epsilon }}\text{,N}{}^{\mathrm{\epsilon }}\text{-}\text{dicarboxy-methyl-}\text{l}\text{-lysine}\text{)}$, which has one tertiary amino and two carboxyl groups in the side chain has been derived from a hydrochloride salt of poly(L-lysine). The polymer in aqueous solution seems to be in the coil form with locally extended structure (LES) at neutral pH. In both the acidic and alkaline regions, the molar ellipticity of the polymer changes as a result of change in net charge on the side chain. The conformational changes may be from the coil with LES to other coiled forms. 5–7 M NaClO₄ and 80% aqueous methanol induce the α-helix in the polymer at neutral pH. Divalent cations, Cu²⁺ and Ca²⁺, do not induce any remarkably ordered structures such as α-helix or β-structure in the polymer in aqueous solution at any pH. Ultraviolet absorption studies show an absorption peak of the polymer-Cu²⁺ complex near 240 nm. Dependence of the peak intensity on pH at various q values ($\text{q =}\text{[}\text{Cu}{}^{\mathrm{2+}}\text{]}\text{[}\text{residue}\text{]}$) indicates the two steps of the complex formation. At q less than 0.64, the formation is described only with the first step. An average coordination number for Cu²⁺ at the first step was calculated to be about 2 by the method of Mandel and Leyte. The association constant of Cu²⁺ with the residue at the step was determined from the absorption data to be far smaller than that for the Cu²⁺-EDTA complex. The second step of the formation occurs in the case of large q but the absorption data for the second step cannot be obtained exactly due to precipitation.     

Sintering of Si3N4-Y2O3-Al2O3

Sintering kinetics of the system Si₃N4-Y2O₃-Al₂O3 were determined from measurements of the linear shrinkage of pressed disks sintered isothermally at 1500° to 1700°C. Amorphous and crystalline Si₃N₄ were studied with additions of 4 to 17 wt% Y₂O₃ and 4 wt% A1₂O₃. Sintering occurs by a liquid-phase mechanism in which the kinetics exhibit the three stages predicted by Kingery's model. However, the rates during the second stage of the process are higher for all compositions than predicted by the model. X-ray data show the presence of several transient phases which, with sufficient heating, disappear leaving mixtures of β ' -Si₃N₄ and glass or β '-Si₃N₄, α '-Si₃N₄, and glass. The compositions and amounts of the residual glassy phases are estimated.     

Participation of lewis base on vinyl chloride polymerization with Al(C2H5)3CCl4 catalyst system

The polymerization of vinyl chloride has been investigated using an $\text{Al}\text{(}\text{C}{}_2\text{H}{}_5\text{)}{}_3\text{CCl}{}_4$ catalyst system in the presence of various Lewis bases. Effective Lewis bases are γ-butyrolactone, diglyme and diethylenetriamine which are multidentate. The rate of polymerization is dependent not only on the basicity of the Lewis base used but also on a coordination number of one. The latter is the predominant factor. For the effect of polymeric amines, a tentative hypothesis is discussed.     

The System Si3N4-SiO2-Y2O3

Subsolidus phase relations were established in the system Si₃N₄-SiO₂-Y₂O₃. Four ternary compounds were confirmed, with compositions of Y₄Si₂O₇N₂, Y₂Si₃O₃N₄, YSiO₂N, and Y₁₀(SiO₄)₆N₂. The eutectic in the triangle Si₃N₄-Y₂Si₂O₇-Y₁₀(SiO₄)₆N₂ melts at 1500°C and that in the triangle Si₂N₂O-SiO₂-Y₂Si₂O₇ at 1550°C. The eutectic temperature of the Si₃N₄-Y₂Si₂O₇ join was ∼ 1520°C.     

Phase Relations in the Pseudobinary System Na2TiSi4O11-Na2Ti2Si2O9

The quenching technique was used to study subliquidus and subsolidus phase relations in the pseudobinary system Na₂ Ti₂Si₂ O₁₁-Na₂ Ti₂ Si₂ O₉. Both narsarukite (Na₂TiSi₄O₁₁) and lorenzenite (Na₂Ti₂Si₂O₉) melt incongruently. Narsarsukite melts at 911°±°C to SiO₂+liquid, with the liquidus at 1016°C. Lorenzenite melts at 910°±5°C to Na₂ Ti₆ O₁₃+liquid; Na₂ Ti₆ O₁₃ reacts with liquid to form TiO₂ and is thus consumed by 985°±5°C. The liquidus occurs at 1252°C.