{"id":42355,"date":"2025-12-17T11:10:43","date_gmt":"2025-12-17T11:10:43","guid":{"rendered":"https:\/\/permabond.com\/?p=42355"},"modified":"2026-01-12T14:33:55","modified_gmt":"2026-01-12T14:33:55","slug":"the-best-adhesive-for-bonding-nylon-to-metal","status":"publish","type":"post","link":"https:\/\/permabond.com\/pt-br\/the-best-adhesive-for-bonding-nylon-to-metal\/","title":{"rendered":"The Best Adhesive for Bonding Nylon to Metal"},"content":{"rendered":"

Bonding nylon<\/a> (chemically known as Polyamide, or PA for short) with adhesives has traditionally been a challenge, as we\u2019ve discussed in previous articles. Key characteristics of nylon which make it tough to bond are its hydrophobicity (resistance to wetting) and hygroscopicity (absorption and internal spreading of moisture from the air around it). Both these factors make it harder for an adhesive to effectively bond nylon and ensure a strong, long-lasting bond.<\/p>\n

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Bonding nylon to metal, however, introduces a new level of challenge. This is because nylon and metals are fundamentally vastly different materials with opposing chemical characteristics. For example, nylon has a medium surface energy, whereas most metals\u2019 surface energy is very high. This causes uneven surface wetting. Nylon also has much higher thermal expansion and contraction than metals, meaning that changes in temperature can create stress on the adhesive bond as the nylon swells and shrinks more than the metal.<\/p>\n

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The same is true with moisture absorption \u2013 as mentioned earlier, nylon is almost hungry for moisture and will readily take this up from the air around it. Metals, on the other hand, do not. Under humidity nylon can therefore swell as it takes in moisture, leading to stress and even breaking of adhesive bonds. Bonding nylon to metal therefore requires an adhesive that can effectively handle these imbalances in characteristics and still provide a strong bond.<\/p>\n

 <\/p>\n\n\n\n\n\n\n\n\n
Property<\/strong><\/td>\nNylon<\/strong><\/td>\nMetals<\/strong><\/td>\nEffect on Bonding<\/strong><\/td>\n<\/tr>\n<\/thead>\n
Surface energy<\/strong><\/td>\nMedium (~40 mN\/m)<\/td>\nVery high (> 1000 mN\/m)<\/td>\nMakes adhesive wetting uneven<\/td>\n<\/tr>\n
Polarity<\/strong><\/td>\nModerately polar (amide groups)<\/td>\nOften non-polar or oxidized<\/td>\nChemical mismatch<\/td>\n<\/tr>\n
Thermal expansion & contraction<\/strong><\/td>\nHigh<\/td>\nLow<\/td>\nThermal cycling stresses the bond<\/td>\n<\/tr>\n
Moisture absorption<\/strong><\/td>\nHigh<\/td>\nLow<\/td>\nNylon swells with humidity, causing stress at the bond<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

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Bonding nylon to metal: Is surface treatment needed?<\/strong><\/h2>\n

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Since nylon can be a bit of a \u2018problem child\u2019 for bonding, traditionally it has needed to be surface treated beforehand. Treatments such as plasma and\/or flame treatment, as well as corona discharge, can be used to simultaneously raise its surface energy and reduce its hygroscopicity. Improvements in these areas can make bonding nylon to metal easier, as they bring the two substrates closer in chemical alignment. Another common surface preparation method is to \u2018dry out\u2019 the nylon before bonding. This can be done by putting it in the oven at 60\u00b0C for 2+ hours (ideally overnight) and then attempting to bond. Unlike with other substrates, simply abrading or roughening the surface offers minimal bond strength improvement. It can provide very slightly more mechanical interlocking, but not enough to constitute anything meaningful.<\/p>\n

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Traditional surface treatment, while effective, can be costly, time-consuming and comes with its own set of risks. Corona discharge creates static, which can attract dust and constitutes a health and safety risk. Flame treatment must be done very carefully to ensure an even treatment and avoid fire risks. Chemical etching, another form of surface treatment, must be done in a fume hood because it is a toxic, corrosive and flammable process.<\/p>\n

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Thankfully, Permabond has developed an adhesive solution for bonding nylon to metal that allows you to avoid surface treatment altogether.<\/p>\n

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The best adhesive for bonding nylon to metal<\/strong><\/h2>\n

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In 2024 Permabond released Permabond TA4550<\/a>, a two-part structural acrylic designed to bond nylon without the need for surface treatment. TA4550 bonds many types of nylon well, including PA6, 6.6 and 12. It cures rapidly at room temperature and its thixotropy means it doesn\u2019t slump or sag post-application, instead staying firmly in place.<\/p>\n

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TA4550 offers several benefits for bonding nylon to metals. Of great importance is its flexibility, giving it the ability to both handle thermal expansion and contraction as well as any swelling of the nylon due to humidity or moisture in the air. Other adhesives would embrittle and eventually break under such conditions, but not TA4550.<\/p>\n

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TA4550 has built-in surface adhesion technology that also allows it to overcome nylon\u2019s hydrophobicity. This means it can fully wet and key into the nylon, ensuring a strong, durable bond. Lastly, TA4550 excels in bonding metals, other plastics and composites, including bonding dissimilar materials \u2013 for example, bonding nylon to metal. This makes it a great all-rounder<\/a> to have in your toolbox for general use, as well as for nylon to metal bonding.<\/p>\n

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The TA4550 difference<\/strong><\/h3>\n

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