摘要 |
<p>Temperature-controlled diffusional active agent dispensers that use a side-chain crystallizable polymer in a form that is not free to flow above its melt temperature as a rate-controlling matrix are disclosed. The polymer may be crosslinked to render it nonflowable, be supported, or grafted to a permeable support. Elements that facilitate or permit heating by radiation or electrical conductance/inductance may be included in the dispenser. At temperatures below the melt temperature of the polymer, the polymer is substantially impermeable to the agent. At temperatures at or above the melt temperature the polymer is substantially permeable to the agent.</p> |