In IP strategy, any isolated IP position of interest to a competitor is likely to be a vulnerable position.  There are many ways to get around it including, but not limited to validity challenges, design around, undetected infringement, calling your bluff on willingness to enforce, countersuits, hostile takeover, picket fence, and leapfrog.  This is why when you protect intellectual property, you should think in terms of an interlinked defense where your IP position can handle the loss of some individual positions without losing IP protection on the whole. For example, a key polymer may be protected by a patent that becomes central to the business model.  Included within the protection of the central patent may be a brand name, a trade secret on production methods, other patents on similar polymers, patents associated with the use of the polymer, defensive publications perhaps on some other uses to prevent one customer from locking up sales to another customer, and perhaps new patents created by new combinations of compounds built off that core polymer invention.

All of these may serve in their way to protect your ability to leverage the propriety of the core invention in the marketplace by making it more challenging for competitors to get around your position.  While strategically you cannot expect to make an IP position that is unassailable to someone with the resources and wherewithal to challenge it.  You can, with reasonable confidence, build an IP position that would be so difficult to challenge that it should be better for rational competitors, partners, and customers, to interact with you concerning that IP on your terms.

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