Functional Characteristics of Polyurethane Adhesive

时间： 2023-04-30 来源：HANSI News

技术问答

选型帮助

研发客服

商务客服

polyurethane adhesives refer to adhesives containing urethane groups (-NHCOO-) or isocyanate groups (-NCO) in the molecular chain. Polyurethane adhesives are divided into two categories: polyisocyanates and polyurethanes. In this article, HANSI will introduce the functional characteristics of polyurethane adhesive.

Polyisocyanate molecular chain contains isocyano group (-NCO) and carbamate group (-NH-COO-), so polyurethane adhesive shows high activity and polarity. It has excellent chemical adhesion with substrates containing active hydrogens, such as foam, plastic, wood, leather, fabric, paper, ceramics, and other porous materials, as well as metal, glass, rubber, plastics, and other materials with smooth surfaces.

Polyurethane adhesive is an important part of the rapidly developing polyurethane resin. It has excellent properties and has been widely used in many aspects. It is one of the important varieties of the eight synthetic adhesives.

Polyurethane adhesives have excellent shear strength and impact resistance properties, are suitable for a variety of structural bonding areas, and have excellent flexibility properties.

Polyurethane adhesive has excellent rubber properties and can adapt to the bonding of substrates with different thermal expansion coefficients. It forms a soft-hard transition layer between the substrates, which not only has strong adhesion but also has excellent buffering, reducing shock function. The low-temperature and ultra-low-temperature performance of polyurethane adhesives exceeds that of all other types of adhesives.

Waterborne polyurethane adhesives have the characteristics of low VOC content, low or no environmental pollution, and non-combustibility, and are the key development direction of polyurethane adhesives.

In 1940, German researchers discovered that triphenylmethane -4, 4'-tri isocyanate can bond metal and sodium butadiene rubber, and was used on tank tracks in World War II. After the 1950s, Bayer developed the Esmorhurs series (diisocyanates and polyisocyanates) and the Esmophens series (low molecular weight hydroxyl terminated polyester polyols). According to a certain amount of esmbd and esmoplen can be formulated into Polystal series of goods (two-component solvent-based polyurethane adhesive).

Japan introduced technology from Germany and the United States in 1954, produced polyurethane materials in 1960, and began to produce polyurethane adhesives in 1966. It successfully developed ethylene-based polyurethane water-based adhesives and put them into industrial production in 1981. The research and production of polyurethane adhesives in Japan is very active, and together with the United States and Western Europe, it has become a major producer and exporter of polyurethane.

China developed and produced triphenylmethane triisocyanate (Lechner glue) in 1956, and soon produced toluene diisocyanate (TDD) and two-component solvent-based polyurethane adhesives. In 1966, polyurethane adhesives were put into production and are still the largest production variety in China's polyurethane adhesives. Since the 1980s, many advanced production lines and products have been introduced from abroad, among which a large number of imported polyurethane adhesives are required to be matched with them. Therefore, domestic research units have been promoted to accelerate the development of polyurethane adhesives, especially after 1986. China's polyurethane industry has entered a period of rapid development. In 1994, state officials approved the establishment of the "China Polyurethane Industry Association", which has a "Polyurethane Adhesive Committee", which has become the national polyurethane adhesive technology and information exchange center.

(1)Classification by reaction composition According to the reaction composition, it can be divided into polyisocyanate adhesives, isocyanate group-containing polyurethane adhesives, hydroxyl-containing polyurethane adhesives and polyurethane resin adhesives.

(2)Classification by use and characteristics According to use and characteristics, it can be divided into general-purpose adhesives, adhesives for food packaging, adhesives for shoes, adhesives for paper-plastic composites, adhesives for construction, structural adhesives Adhesives, adhesives for ultra-low temperature, foaming adhesives, anaerobic adhesives, conductive adhesives, hot-melt adhesives, pressure-sensitive adhesives, sealing adhesives water-based adhesives and sealants.

No matter what kind of polyurethane adhesive, the isocyanate group in the system reacts with the substance containing active hydrogen in or outside the system to generate a polyurethane group or polyurea so that the strength of the system is significantly improved to achieve the purpose of bonding.

High-performance waterborne polyurethane adhesives have the following characteristics:

(1)Good water resistance and medium resistance.

(2)High bonding strength and large initial adhesion.

(3)Good storage stability.

(4)Freeze-thaw resistance and high-temperature resistance.

(5)The drying speed is fast, and the film-forming property is good at low ambient temperatures.

(6)The construction technology is good.

To achieve the above points, in addition to synthesizing high-performance waterborne polyurethane, the selection of film formulation assistants is also particularly important.

The synthetic raw materials of polyurethane prepolymers are mainly oligomer polyols and diisocyanates. Oligomer polyols are usually divided into two categories: polyether polyols and polyester polyols. The prepolymers prepared from polyether polyols have good hydrolytic stability, good flexibility and extensibility, and low-temperature resistance. Good; while polyester polyol type prepolymer has large cohesion and high bonding strength.

How to use polyurethane adhesive

Kenuo chemical polyurethane adhesive has the advantages of high solid content, low viscosity, good process applicability, strong adhesion, non-toxic, etc.

发送到邮箱 |
+1 赞 0
收藏
评论 0
| 转发至：

本文由上山打老虎转载自HANSI News，原文标题为:Functional characteristics of polyurethane adhesive，本站所有转载文章系出于传递更多信息之目的，且明确注明来源，不希望被转载的媒体或个人可与我们联系，我们将立即进行删除处理。

全部评论（0）

暂无评论

Polyurethane Adhesive Construction Technology

There are often weak interface layers such as grease and dust on the surface of the adherend. Affected by them, the bonding strength obtained by bonding on the weak treatment is one of the first steps to improving bond strength.

技术探讨发布时间 : 2023-04-27

Classification of Industrial Glues

In this article, HANSI will introduce the classification of industrial glues.

技术探讨发布时间 : 2023-04-26

【技术】水性胶的储蓄和使用注意事项

随着水性胶的普遍使用，那有关水性胶的储蓄跟使用注意事项大家都知道吗？下面让汉司的小编来告诉大家：汉司水性胶的储蓄：1、储存和运输应在0℃~50℃，并避免阳光照射；低于0℃胶的分子结构容易发生变化，从而使胶水性能减弱甚至失效。

技术探讨发布时间 : 2023-04-29

全品类胶粘剂产品，高可靠性/高韧性/可调固化/易返修，满足个性化定制需求

世强硬创联合德聚、汉司、禧合、金菱通达、视焓科技、金芯诚、SUNSTAR带来具有高可靠性/高韧性/可调固化/易返修等优势的全品类胶粘剂产品，品类覆盖粘接、结构、灌封、密封、导电、底填、固晶等，可满足客户定制化需求。

活动发布时间 : 2023-08-28

【材料】汉司全新汽车碳纤维材料粘接结构胶的革新力量，提供高韧性和高粘接强度，室温固化/加热可提升固化效率

胶接是目前碳纤维复合材料连接的主流手段，目前碳纤维复合材料常用的粘合剂是环氧树脂类、聚氨酯类、丙烯酸类。汉司粘合剂针对碳纤维材料在汽车领域的应用做了深度探索，适应市场需求的创新，推出两款全新产品：MegaGlue® 4006/B20和YEBOND® 3008系列产品。

产品发布时间 : 2023-12-26

2024慕尼黑上海电子展：汉司精彩时刻重现

Electronica China 2024 已圆满落幕，精彩却仍历历在目！汉司电子携创新的电子粘合剂解决方案强势来袭,“创新技术+专业服务”，为您精心打造一站式整体粘接和密封解决方案.

厂牌及品类发布时间 : 2024-09-10

【产品】无溶剂型双组分聚氨酯胶粘剂MegaCast®6004/B，具备自熄灭、高导热、电绝缘和抗震功能

汉司MegaCast®6004/B是一种无溶剂型双组分聚氨酯胶粘剂。主剂是一种含羟基的预聚物，固化剂是一种改性的预聚物；主、固剂按100：16的重量比混合，固化后得到含导热和阻燃功能的聚氨酯密封材料。

产品发布时间 : 2023-08-04

汉司湖北新材料产业园奠基开工，环评产能和实际产能达到年产6万吨，产品种类增加，辐射更多客户群体！

汉司湖北新材料产业园新厂区建成后，环评产能和实际生产产能进一步扩大，达到年产6万吨；产品种类增加，从现有的聚氨酯和改性硅烷粘合剂，延伸至环氧、丙烯酸酯及水性粘合剂等多元化产品。辐射范围扩大至华东地区、华中地区，以及华中地区500公里范围内的客户群体。

厂牌及品类发布时间 : 2024-05-24

汉司携创新解决方案亮相2024中国国际复合材料展

面对复材行业层出不穷的创新与变革，汉司凭借强劲的研发实力“以变应变”。无论是特殊环境的耐受性需求，还是复杂结构的粘接挑战，从环保配方到高强度粘接技术，我们都能为您量身定制，卓越的粘合剂解决方案。即将到来的复材展是我们展示创新研发成果和产品实力的绝佳舞台。我们的粘接技术将助力复合材料在航空航天、轨道交通、海洋船舶、车辆装配、汽车内饰、风电能源等多个应用领域的极端挑战。

厂牌及品类发布时间 : 2024-09-09