Лако-красочные материалы — производство

Adhesives are mostly thermoset plastics when cured (although cyanoacrylates are thermoplastic) and in any case are a highly complex polymer. In most engineering applications, the mass of adhesive within an assembly or sub-assembly is negligible and only a few percent of the total mass of the component and it will be difficult (and very expensive) […]

This section does not attempt to discuss the health and safety of engineering adhesives in full detail but merely gives an overview of some of the regulations and major precautions that may need to be considered when selecting adhesives for the bonding of engineering plastics or elastomers. The H&S issue is quite rightly increasingly becoming […]

One of the benefits of adhesives is that they will fill gaps between poorly fitting parts or parts with large manufacturing tolerances. The cure of epoxies is not affected by the gap between the parts but cyanoacrylates are very much driven by this gap and are limited to gaps of less than 0.2 mm. The […]

On some production lines a very fast curing adhesive is necessary to minimise work- in-progress. But in other applications where alignment of the parts is difficult a longer cure may be necessary and this may be achieved by using a ‘cure-on-demand’ UV-curing adhesive. The cure speed of two-part acrylics is typically in the range of […]

The viscosity of the adhesive can also be a significant factor in adhesive selection. Low — viscosity adhesives (<50 mPa-s) should be used where gaps are small and the adhesive is required to flow or wick into parts that have been pre-assembled. A medium — viscosity adhesive (up to 1000 mPa-s) may be more appropriate […]

The joint design is fundamental to the integrity and efficacy of the performance of the adhesive. Some detailed notes on joint design are given in Chapter 5, but it is important to try and understand all the forces that the adhesive is being subjected to. In practice, this means that the nature and magnitude of […]

The suitability of an application procedure will be an important consideration in the selection of an adhesive. It is not sufficient that an adhesive can provide the necessary performance. It must also be possible to apply the adhesive at the required location and at an acceptable cost. Single-part, fast-cure adhesives such as cyanoacrylates are ideal […]

Most adhesives will operate within the range -40 °C to 120 °C and speciality grades will operate to higher temperatures. A room-temperature-vulcanising silicone will often be suitable up to >250 °C. On the other hand a standard ethyl based cyanoacrylate will only operate to about 90 °C. A significant point to consider when selecting an […]

Perhaps one of the most fundamental and key properties associated with the selection of the adhesive is to make sure that it bonds well to the two materials selected. Cyanoacrylates generally have good affinity to plastics and a good number of ultraviolet (UV) adhesive grades are also particularly suited for plastics, whilst other UV adhesives […]

Factors that may need to be considered for the selection of an appropriate adhesive include the following: • Selection of materials, • Adhesive performance, ° Tensile strength, ° Peel strength, ° Impact loading, • Durability and long-term performance, • Temperature resistance, • Surface preparation, • Ease of application, • Joint design, • Cure speed and […]