Acoustic sensors and methods

An acoustic sensor comprising a soluble polymer having two or more pendant groups independently selected from the group consisting of functional groups having the following formulas:

• wherein:
• R1 and R2 together with a dicarboximide group to which they are attached form a four to eight membered heterocyclic or heterobicyclic group that can be fused to an optional aromatic group, optional saturated or unsaturated cyclic group, or optional saturated or unsaturated bicyclic group;
• R3 is an alkyl, aryl, aralkyl, or —NRaRb wherein Ra and Rb are each an alkyl group or taken together with the nitrogen atom to which they are attached form a four to eight membered heterocyclic group;
• R4 and R5 together with a dicarboximide group to which they are attached form a four to eight membered heterocyclic or heterobicyclic group that can be fused to an optional aromatic group, optional saturated or unsaturated cyclic group, or optional saturated or unsaturated bicyclic group;
• R6 is an alkyl, fluoroalkyl, chloroalkyl, aryl, —NRcRd wherein Rc and Rd are each an alkyl group or taken together with the nitrogen atom to which they are attached form a four to eight membered cyclic group, or R6 taken together with Re and the groups to which they are attached form the four to eight membered heterocyclic or heterobicyclic group that can be fused to the optional aromatic group, optional saturated or unsaturated cyclic group, or optional saturated or unsaturated bicyclic group;
• Z is an alkyl, aryl, or —(CO)Re wherein Re together with R6 and groups to which they are attached form a four to eight membered heterocyclic or heterobicyclic group having a nitrogen heteroatom and a sulfur heteroatom, wherein said heterocyclic or heterobicyclic group can be fused to an optional aromatic group, optional saturated or unsaturated cyclic group, or optional saturated or unsaturated bicyclic group;
• Y1, Y2, and Y3 are each independently a single bond or a divalent group selected from the group consisting of an alkylene, heteroalkylene, arylene, carbonyl, carbonyloxy, carbonylimino, oxy, thio, —NRf— where Rf is hydrogen or alkyl, and combinations thereof;
• and
• Y4 and Y5 are each a bond.

A method of coating an acoustic sensor, the method comprising:

• applying a soluble polymer to a surface of the acoustic sensor using a non-contact deposition technique, wherein the soluble polymer has two or more pendant groups independently selected from the group consisting of functional groups having the following formulas:
• wherein:
• R1 and R2 together with a dicarboximide group to which they are attached form a four to eight membered heterocyclic or heterobicyclic group that can be fused to an optional aromatic group, optional saturated or unsaturated cyclic group, or optional saturated or unsaturated bicyclic group;
• R3 is an alkyl, aryl, aralkyl, or —NRaRb wherein Ra and Rb are each an alkyl group or taken together with the nitrogen atom to which they are attached form a four to eight membered heterocyclic group;
• R4 and R5 together with a dicarboximide group to which they are attached form a four to eight membered heterocyclic or heterobicyclic group that can be fused to an optional aromatic group, optional saturated or unsaturated cyclic group, or optional saturated or unsaturated bicyclic group;
• R6 is an alkyl, fluoroalkyl, chloroalkyl, aryl, —NRcRd wherein Rc and Rd are each an alkyl group or taken together with the nitrogen atom to which they are attached form a four to eight membered cyclic group, or R6 taken together with Re and the groups to which they are attached form the four to eight membered heterocyclic or heterobicyclic group that can be fused to the optional aromatic group, optional saturated or unsaturated cyclic group, or optional saturated or unsaturated bicyclic group;
• Z is an alkyl, aryl, or —(CO)Re wherein Re together with R6 and groups to which they are attached form a four to eight membered heterocyclic or heterobicyclic group having a nitrogen heteroatom and a sulfur heteroatom, wherein said heterocyclic or heterobicyclic group can be fused to an optional aromatic group, optional saturated or unsaturated cyclic group, or optional saturated or unsaturated bicyclic group;
• Y1, Y2, and Y3 are each independently a single bond or a divalent group selected from the group consisting of an alkylene, heteroalkylene, arylene, carbonyl, carbonyloxy, carbonylimino, oxy, thio, —NRf— where Rf is hydrogen or alkyl, and combinations thereof;
• and
• Y4 and Y5 are each a bond.