高速铁路用热塑性聚酯弹性体发泡材料挤出成型研究

采用挤出成型工艺制备热塑性聚酯弹性体(TPEE)发泡材料。研究了发泡剂的用量,成核剂的种类和用量,交联剂对TPEE挤出发泡材料性能的影响。采用万能力学测试机和扫描电子显微镜分别测试和观察了TPEE发泡材料的力学性能和泡孔结构,并测试了TPEE发泡材料的表观密度。结果表明:TPEE发泡材料的性能与发泡剂用量之间的关系并不是简单的线性关系;恰当的成核剂种类和用量能够为发泡体系提供大量的成核点,进而利于均匀泡孔的生成;加入过氧化二异丙苯(DCP)可提高发泡材料的力学性能,但降低了发泡率和均匀性;合理的加工参数对得到优质的TPEE发泡材料极为重要。综合考虑,当发泡体系中偶氮二甲酰胺(AC)为0.8份,苯甲酸钠为1.6份,采用压缩比为3:1的销钉式单螺杆挤出机,转速为70r/min,挤出温度为205℃,并且不加入DCP的工艺条件下制得的TPEE发泡材料的泡孔结构更为规整,整体性能更为理想。     

Performance of Φ-Sulfo Fatty Methyl Ester Sulfonate Versus Linear Alkylbenzene Sulfonate,Secondary Alkane Sulfonate and α-Sulfo Fatty Methyl Ester Sulfonate

Sulfoxidation of fatty acid methyl esters with SO_2, O₂ and ultraviolet light of appropriate wavelength, has led to the synthesis of methyl esters sulfonates or sulfoxylates, known as Φ-MES, because of the possible random position of SO₃ group in the alkyl chain. Aqueous solutions based on the sulfoxylated methyl ester of palmitic acid (Φ-MES C16) have been studied and compared to the leading types of surfactants used today: linear alkylbenzene sulfonate (LAS) secondary alkane sulfonate (SAS) and α-sulfo fatty methyl ester sulfonate (α-MES) with regard to solubility, performance and skin compatibility. The experimental results obtained indicate that Φ-MES C16 can be regarded as a potential component of detergent formulations and most likely also of body care products.

橡塑共混乒乓板用海绵的研制

较为详尽地叙述了ＮＲ／ＥＶＡ共混海绵制品的研制情况,对其橡塑比、发泡体系及硫化工艺等方面的选择进行了讨论,并阐明了产品的制造过程及共效果。     

HCFC—141b发泡工艺及冰箱内衬材料的选择

介绍了HCFC-141b发泡工艺和泡沫性能,对影响泡沫制品质量的因素及抗HCFC-141b的新型ABS材料选择问题进行讨论。     

Rheological control in foaming polymeric materials: I. Amorphous polymers

The influence of rheological properties, especially melt strength, on foam structures, such as cell size, cell density and cell size distribution, of amorphous polymer was investigated. The rheology of polystyrene (PS) was controlled by molecular modification with free radical reaction, and PS with long chain branching (LCB) level ranging from 0.15 to 1.6 branching point per 10⁴ carbon atom was gotten. The shear and elongational rheology were found to be dependent on the LCB structure, and the strain hardening behavior of modified samples in transient elongational viscosity confirmed the existence of long branched chain. The effects of chain structure and foaming conditions such as temperature and pressure were studied by the analysis on the foam structures obtained by supercritical CO₂. The experimental results revealed that increasing LCB level would decrease cell size, make cell size distribution narrower and slightly increase cell density. The effects of chain topology on the foam structures were also investigated by numerical simulation, where Pom-Pom model was used to describe the effect of backbone length and arm length. The dependence of cell size on the arm length was consistently observed in experiments and simulation. It suggested that the arm length had greater influence on the cell radius than the backbone length. Therefore, the relationship among foam structures, rheological properties and molecular structures can be established from both experiments and simulation, which can be used as a guidance to control the foam structure by designing and controlling the molecular structures and the corresponding rheological properties.     

Evaluation of Non-Ambiguous Critical Micelle Concentration of Surfactants in Relation to Solution Behaviors of Pure and Mixed Surfactant Systems: A Physicochemical Documentary and Analysis

Critical micelle concentration (CMC) is a fundamental physical parameter of surfactant aggregation in solution. The CMC is determined by different methods, tensiometry, conductometry, microcalorimetry, fluorimetry, and so on. However, it is known that though CMC is reported as a single value, in reality, micelle formation occurs over a narrow range of concentration for different experimental procedures produce different results. We shall discuss about a unique procedure of measuring correct CMC applicable to all potential methods used in practice. This is essential for the evaluation of thermodynamic properties of the micelle forming process in pure and mixed states in terms of solution theories. As we in this short documentary want to deal with various aspects of Milton Rosen's research—wherein we have also worked—a few other facets of surfactant chemistry research, besides the micelle formation, are also briefly discussed. In mixed surfactant systems, synergistic effects in various surfactant properties like detergency, foaming, solubilization, and so on are found whereas in some others non-synergistic effects are observed. Dehydration of micelles with an increase in temperature or by the addition of hydrophilic substances may cause clouding to the system. Soluble amphiphilic systems produce Gibbs monolayer at the air/water interface; insoluble amphiphiles form Langmuir monolayers. A documentary of the above aspects will be herein presented and discussed. We mention that this article is neither an original research article nor a review article. This is a mixture of the two: a documentary of both original research and some review of our works presented in memory of Prof. Milton Rosen.     

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在对MDEA溶液中各种杂质组分的分析基础上，通过发泡实验考察了操作条件及各种杂质组分对溶液发泡性能的影响。随着MDEA浓度、MDEA溶液温度的逐渐降低，发泡高度及消泡时间逐渐增大；另外随着通气流率和溶液中CO₂负荷的增大，MDEA溶液发泡高度及消泡时间也逐渐增大。考察了NaCl、CaCl₂、FeSO₄无机盐对MDEA溶液发泡性能的影响。MDEA溶液中有机杂质甲醇、三甘醇、重烃对MDEA溶液则具有一定的消泡作用，而气井缓蚀剂无疑是强的发泡剂。残液的加入使纯净的MDEA溶液发泡性能大幅度地增加，验证了MDEA溶液受到了污染是造成溶液发泡的主要原因。最后对MDEA溶液发泡提出了相应的处理措施和建议。     

某高镁磷尾矿矿石工艺特性研究

对某磷矿尾矿的物相和化学组成、反应特性及发泡性能进行了研究。结果表明:该尾矿的主要物相为CaMg(CO3 )2、Ca5F(PO4 )3,MgO含量为19. 0%、P2O5 含量为5. 94%;尾矿的反应活性较好,抗阻缓性较差,发泡比较严重,加入消泡剂BMS-1后,发泡明显减弱。     

Functionality of egg white proteins as affected by high intensity ultrasound

The goal of this contribution was to determine the impact of HIUS on the thermal aggregation, gelation, foaming and emulsifying properties of egg white (EW) proteins.