Hybrid Coatings Increase Hardness of Plastic and Allow Properties to be Tailored

Mechanical behaviour of hybrid SiO₂-PMMA coatings measured by nanoindentation

Increasing the surface hardness of many materials opens them up for use in a wide variety of new applications. These new hybrid materials could be used in areas like anticorrosion coatings for metals, scratch and abrasion resistant coatings for plastics, antistatic films plus colour decorative coatings for glasses and plastics.

The sol-gel method of materials preparation is a suitable technique that can be used to obtain composite materials with reinforced properties and produce hybrid coatings. It is capable of producing materials that combine the complementary properties of the inorganic and organic materials.

Engineering plastics such as polymethylmetacrylate or PMMA are distinct candidate materials that can benefit from reinforcement with inorganic materials. Silica (SiO₂), is a suitable reinforcing material that was used in this investigation.

In this paper researchers from Universidad Autonoma de Sinaloa, Fuente de Poseidon y Prol and Centro de Investigacion y Estudios Avanzados del Instituto Politécnico Nacional, J.L. Almaral-Sanchez, M. Lopez-Gomez, R. Ramirez-Bon, J. Munoz-Saldana,准备的混合动力SIO₂- 使用Sol-Gel方法和测量涂层硬度的PMMA涂料。他们应用了两个深度传感凹痕（DSI）系统，每个系统都使用具有不同几何形状和大小的凹痕来分析SIO杂交涂层的机械行为₂- 具有不同摩尔比的PMMA。采用压痕模型，使用两个系统作为混合膜的PMMA含量进行了评估涂料的绝对硬度。

从凹痕测量结果中，研究人员发现，与常规丙烯酸相比，杂交涂料的机械性能得到了改善。杂化涂层的硬度从三倍到一个以上的数量级高于丙烯酸硬度，具体取决于摩尔比。在涂料表面测量了一种额外的硬化现象，这可能是由于该区域富集了二氧化硅。最终，他们发现涂料的硬度随PMMA含量而单调的降低。这些结果使混合涂层可以使用针对单个应用的机械性能制成。

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