In order to activate the polymers for electroless copper deposition, an alternative way of sample preparation is demonstrated. The samples are prepared by incorporation of a small amount (<1 wt %) of palladium, nickel, or copper acetate into the molten Liquid Crystal Polymer (LCP) in a blender. Since the blending temperature is kept higher than the decomposition temperature of acetates, the acetates are thermally decomposed during blending, leading to the metallic Pd, Ni, or Cu which are used as activators for electroless deposition. After preparing the samples, electroless copper deposition is successfully realized. The influence of different acetates (Pd, Ni, or Cu acetates) on the deposition is investigated. The copper amount is higher and the deposition kinetics is faster on LCP samples with 0.15 wt % Pd and 0.4 wt % Ni than that with 0.4 wt % Cu. The deposited copper layers are uniform and oxide-free. Moreover, the possibility to substitute expensive Pd activator by cheaper Ni or Cu is shown.

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Upgraded biodegradable piezoelectric composite materials elaborated by incorporation of Rochelle salt (RS, Sodium potassium tartrate tetrahydrate) in wood were reported. RS crystals, known as the first discovered piezoelectric material, were grown in the micro-cavities of wood, having naturally a tubular structure, by soaking the wood into RS saturated water. Since most of the cavities in wood are oriented in the same direction, the piezoelectric effect was improved when the cavities were filled by RS crystals. The mechanical, structural and piezoelectric properties of RS incorporated wood composite samples were characterized. Both direct and converse piezoelectric effects are illustrated. The wood-base composite exhibits an effective piezoelectric constant d33 of 11 pC N−1. Also, the flexural strength and modulus of elasticity were enhanced by inserting RS into the wood, nevertheless the samples became more brittle. The wood-based piezoelectric samples prepared in this work can be used as actuators, sensors or energy harvesters. The process developed here permits us to manufacture large area piezoelectric devices which are environmentally and economically unsurpassed.