纤维对水基泡沫液稳定性影响的研究

探讨了蔗渣浆、阔叶木浆和针叶木浆漂白后的纤维原料对水基泡沫液的发泡能力和稳定性的影响,并采用光学显微镜与Image J软件结合的方法,着重研究了水基泡沫液中气泡大小及其分布情况。结果表明,较宽的纤维长度分布有利于水基泡沫液的发泡性能;纤维长、多分散性数值大的水基泡沫液的稳定性好,气泡直径较小且大小均匀;3种浆料中,蔗渣浆纤维的水基泡沫液稳定性最差,其次是阔叶木浆纤维的水基泡沫液,针叶木浆纤维的水基泡沫液稳定性最好。     

水基泡沫的稳定性评价技术及影响因素研究进展

综述了当前比较常用的和新开发的泡沫稳定性评价技术,评述了水基泡沫稳定性的影响因素,并对改变泡沫稳定性的途径进行了探讨,同时展望了有关泡沫稳定性研究的发展方向。     

泡沫性能的测试和评价方法进展

综述了测试泡沫性能——主要是溶液的起泡能力和泡沫稳定性的方法以及评价手段；介绍了常用的起泡方式及检测手段，包括体积法、电导率法和压力法，讨论了各方法的优缺点；并叙述了评价溶液起泡能力和泡沫稳定性手段的进展；提出了选择合理的评价方法以客观完善的对泡沫性能进行评价的必要性。     

日用化学品泡沫性能的多维度评价方法研究

介绍了动态泡沫分析的测试方法和测试原理，并开展了表面活性剂常用原料、洗衣液、洗发水和牙膏等常规日化产品的泡沫性能研究。在动态泡沫的测试中，基于不同样品设置了差异化的测试程序，监测了整个测试周期内泡沫高度、泡沫体积、每平方毫米气泡个数、气泡平均面积、气泡平均半径等参数随时间的演化关系，计算出体积消泡率、气泡个数变化率等反映泡沫稳定性的相关参数。利用高度测试模块中泡沫体积、泡沫高度等参数的分析评价了各样品的发泡能力；通过结构测试模块中气泡个数、平均气泡面积、平均气泡半径等参数的分析评价了各样品的泡沫微观特性；同时结合高度测试和结构测试双模块中持久值、体积消泡率、气泡个数变化率、半衰期等多角度评价了各样品的泡沫稳定性。由此经双模块测试中各参数的协同分析实现了产品发泡快慢、泡沫多少、泡沫大小和稳定性等泡沫性能的多维度评价。     

泡沫起泡性、稳定性及评价方法

本文论述了泡沫的两个基本性质:起泡性和稳定性。对起泡性和提高泡沫稳定性的方法作了评价。     

油相对含氟磺基甜菜碱泡沫性能影响研究

为了研究油相对氟碳表面活性剂泡沫性能的影响,使用气流法探讨了含油量和气液比对不同浓度的含氟磺基甜菜碱体系的泡沫性能,并通过测量表面与界面张力来分析该泡沫体系在油作用下的消泡方式。结果表明,在表面活性剂质量浓度由0.3%减至0.05%,含油体积由10%增至40%,气液比由3∶1减至1∶3的各个过程中,泡沫的起泡能力和稳定性都下降,一定条件下起泡能力受泡沫稳定性影响。发现假乳状液膜理论能很好的解释泡沫稳定性实验结果。在该泡沫体系中油通过形成不稳定的油桥使泡沫膜破灭。     

油相对含氟磺基甜菜碱泡沫性能影响研究

为了研究油相对氟碳表面活性剂泡沫性能的影响,使用气流法探讨了含油量和气液比对不同浓度的含氟磺基甜菜碱体系的泡沫性能,并通过测量表面与界面张力来分析该泡沫体系在油作用下的消泡方式。结果表明,在表面活性剂质量浓度由0.3%减至0.05%,含油体积由10%增至40%,气液比由3∶1减至1∶3的各个过程中,泡沫的起泡能力和稳定性都下降,一定条件下起泡能力受泡沫稳定性影响。发现假乳状液膜理论能很好的解释泡沫稳定性实验结果。在该泡沫体系中油通过形成不稳定的油桥使泡沫膜破灭。     

个人护理用品泡沫性能的检测

综述了个人护理用品泡沫性能测试的通行方法，介绍了各种方法的操作及检测特点，阐明了借助仪器设备进行泡沫性能测定的方法可以快速得到有关产品起泡性或泡沫稳定性的数据，但要了解消费者对泡沫型产品的期望和认可程度还足要进行泡沫的主观评价测试。     

泡沫完井液的研究与应用

论述了泡沫的两个基本性质:起泡性和稳定性。对起泡性和提高泡沫稳定性的方法作了评价。通过对发泡剂及稳泡剂的筛选,研制出了低密度泡沫完井液的配方。试验结果表明:此泡沫完井液体系密度可控(0.6~0.75 g/cm3)、稳定时间长,具有很好的储层保护效果。     

泡沫玻璃常温耐碱性能研究

泡沫玻璃是一种具有良好综合特性的保温材料,目前在建筑保温的应用已经逐步开始,本文主要研究了泡沫玻璃在常温碱环境下的稳定性,通过质量损失、X-RD和扫描电镜进行了分析,并通过强度试验验证了泡沫玻璃外墙保温体系的耐碱性能。     

表面活性剂浓度对泡沫体系稳定性的影响

主要探讨了在泡沫体系内,表面活性剂对泡沫稳定性的影响,以表活剂浓度为主要研究点,总结了不同表活剂浓度下气泡的聚并过程,还分析了液膜的排液过程,指出界面流变学因素以及表活剂高浓度情况下的胶束分层现象是影响泡沫稳定的主要因素.表活剂浓度低于CMC时,界面流变学因素起主要决定作用;表活剂浓度高于CMC时,胶团分层起主要决定作用.     

Influence of Hydrocarbon Chain Branching on Foam Properties of Olefin Sulfonate with FoamScan

The influence of surfactant structure on foam properties of internal olefin sulfonate (IOS) and alpha olefin sulfonate (AOS) in aqueous solutions was estimated from measurements of the foamability, foam stability, and foam morphology, as obtained from conductivity and image analyses techniques. It was found that the foamability and foam stability of C_16–18 AOS are higher compared to that of C_16–18 IOS, indicating that hydrocarbon chain branching decreases the foamability and foam stability. The foamability and foam stability are enhanced with increasing surfactant concentration, which increases the adsorbed quantity of surfactant molecules at the air–water interface. The influence of hydrocarbon chain branching on foam morphology was also investigated. It was found that foam cells produced by branched chain C_16–18 IOS are larger than the foam cells generated by straight chain C_16–18 AOS.     

Mechanism Study on the Severe Foaming of Rhamnolipid in Fermentation

Although the biosurfactant rhamnolipid has been previously characterized as having low foam ability, its fermentation is largely impeded by severe foaming. Hence, the investigation of this paradox is critically important for improving the mass production of rhamnolipid. Unexpectedly, the hydrophobic cell, instead of rhamnolipid, has been claimed to explain such severe foaming in rhamnolipid fermentation. This study tried to systematically investigate the severe foaming in fermentation, aiming to propose an effective strategy for foam control. The overflowing foam sustained a super high stability in terms of half‐time for over 30 min. The major product of rhamnolipid largely contributed to the severe foaming in the fermentation process whereas other products like cells elicited much more limited effects. Furthermore, the foam stability of the fermentation broth increased with rhamnolipid concentration and noticeably increased with agitation speed. In the classic Bikerman foam test system without stirring, rhamnolipid showed foam stability as low as Tween 20 which is well known for its poor foam stability. However, in a stirring Bikerman system, rhamnolipid exhibited a foam stability almost as high as sodium dodecyl sulfate (SDS) at 10 g/L and even surpassed SDS at a higher concentration of 20 g/L. Hence, the extraordinarily increased foam stability of rhamnolipid with both agitation and concentration could explain the severe foaming at its late‐stage fermentation when rhamnolipid‐rich solution is mechanically agitated.     

Analysis of the Effects of Hydrocarbon Chain on Foam Properties of Alkyl Polyglycosides

The influence of surfactant structure on foam properties of different alkyl polyglycosides (APGs) in aqueous solutions was studied. Foamability, foam stability, and foam morphology were analyzed using the FoamScan method. Results showed that the foamability, foam stability, and the liquid carrying ability of long-chain APGs are higher than those of short-chain APGs. Foam morphology analysis showed that the foam produced by short-chain APGs is more unstable than the foam generated by long-chain APGs. Long-chain APGs have stronger intermolecular cohesion force, stringency, and ductility than short-chain APGs.     

Foam-Mat Freeze Drying of Egg White and Mathematical Modeling Part I Optimization of Egg White Foam Stability

Egg white (albumen) is a rich source of protein and is widely used in confectionary industry for its wonderful foaming ability. Foam-mat freeze drying is one of the promising methods of drying, which tries to utilize the advantages of both freeze drying and foam-mat drying to produce better quality egg white powder. Preliminary experiments showed that the stability of foams made with egg white alone is not adequate for foam-mat freeze drying. Experiments were thus conducted using different stabilizers (methyl cellulose, propylene glycol alginate, and xanthan gum) to optimize foam stability. Bubble size distribution was determined using microscopy to understand foam structure. This article will discuss the effect of stabilizers on the stability of egg white foam and possible mechanisms involved. The results showed that xanthan gum at 0.125% provided sufficient stability for freeze drying.     

Foam-Mat Freeze Drying of Egg White and Mathematical Modeling Part I Optimization of Egg White Foam Stability

Egg white (albumen) is a rich source of protein and is widely used in confectionary industry for its wonderful foaming ability. Foam-mat freeze drying is one of the promising methods of drying, which tries to utilize the advantages of both freeze drying and foam-mat drying to produce better quality egg white powder. Preliminary experiments showed that the stability of foams made with egg white alone is not adequate for foam-mat freeze drying. Experiments were thus conducted using different stabilizers (methyl cellulose, propylene glycol alginate, and xanthan gum) to optimize foam stability. Bubble size distribution was determined using microscopy to understand foam structure. This article will discuss the effect of stabilizers on the stability of egg white foam and possible mechanisms involved. The results showed that xanthan gum at 0.125% provided sufficient stability for freeze drying.     

聚氨酯包装泡沫的研制

以高活性聚醚多元醇、硬泡聚醚多元醇、发泡剂、助剂及混合多异氨酸酯为原料,制备了密度为8~10kg／m3的包装用聚氨酯泡沫。讨论了影响泡沫性能的因素。     

Study of Foaming Properties and Effect of the Isomeric Distribution of Some Anionic Surfactants

Using different reaction conditions of photosulfochlorination of n-dodecane, two samples of anionic surfactants of sulfonate type are obtained. Their micellar behavior has been already reported and the relationship between their isomeric distribution and their chemical structures and micellar behaviors have been more thoroughly explored. In this investigation, we screened the foaming properties (foaming power and foam stability) by a standardized method very similar to the Ross–Miles foaming tests to identify which surfactants are suitable for applications requiring high foaming, or, alternatively, low foaming. The results obtained for the synthesized surfactants are compared to those obtained for an industrial sample of secondary alkanesulfonate (Hostapur 60) and to those of a commercial sample of sodium dodecylsulfate used as reference for anionic surfactants. The foam formation and foam stability of aqueous solutions of the two samples of dodecanesulfonate are compared as a function of their isomeric distribution. These compounds show good foaming power characterized in most cases by metastable or dry foams. The highest foaming power is obtained for the sample rich in primary isomers which also produces foam with a relatively high stability. For the sample rich in secondary isomers we observe under fixed conditions a comparable initial foam height but the foam stability turns out to be low. This property is interesting for applications requiring low foaming properties such as dishwashing liquid for machines. The best results are observed near and above the critical micellar concentrations and at 25 °C for both the samples.

聚苯乙烯泡沫作为风电叶片夹芯材料的可行性研究

讨论了聚苯乙烯(PS)泡沫在风电叶片中的应用,通过对比研究聚氯乙烯(PVC)泡沫和PS泡沫本体以及泡沫玻璃钢夹芯结构的力学性能,通过有限元模拟夹芯结构悬臂梁在加载后发生的位移值来判断PS泡沫作为夹芯结构的芯材对整体刚度的影响,并通过实验测量和有限元模拟泡沫夹芯结构。结果显示,PS泡沫本体力学性能较PVC低;PS泡沫作为夹芯结构的芯材可以使用在叶片的剪切腹板中,在替代PVC泡沫使用在壳体蒙皮的夹芯层中,若要保证蒙皮的刚度不变则需要增加PS泡沫的厚度。     

酚醛泡沫塑料制备和性能研究

研究了酚醛泡沫制备工艺中一些参数条件对泡沫体性能的影响。研究发现：泡沫体的密度随发泡剂的用量增大而减小；表面活性剂的最适合用量为树脂质量的5％；固化剂的用量为树脂质量的4％-6％时可以达到发泡和固化同步的效果。泡沫体的吸水率与泡沫体的密度相关。力学实验表明：泡沫体的压缩强度随泡沫体的密度增大而增大。热重分析结果表明：泡沫体具有优秀的热稳定性能。