After 100 years, the sector is still growing vigorously. Much of the plastics technology used today is new, and there is still a great deal to be learned. Use of new products, processes and applications that are continually being developed creates a great deal of technological uncertainty.

Most SR&ED in the plastics sector is experimental development, designed to create new or improve existing materials, devices, products or processes. As a result, most claims are for experimental development. The scientific advancements, on which these technological advancements depend, take place primarily in other sectors or at academic institutions. For example resins and the catalysts for producing them are developed at companies that are part of the chemical sector, while fundamental molecular level studies take place mainly in universities.

Where companies include "basic research" projects in their SR&ED claims, it is usually easy for them and the CRA technical reviewers to agree on the nature and extent of the work. Neither CRA nor the claimants see the SR&ED in "applied research" or "experimental development" as easily.

Most of the science available to the plastics sector is descriptive rather than predictive. Even when some basic principles are known, new combinations of materials and processes often produce unexpected outcomes; application of these known principles is often fraught with uncertainty.

In the plastics sector, a general technology will often exist, but the technology for individual applications must still be developed. This is why some R&D activities in the plastics industry appear at first glance to be routine engineering development. In fact there can be a great deal of technological uncertainty.