PHB (OR polyhydroxybutyrate) has been developed for a long time. During 1923-1927, Maurice Lemoigne researched about using bacteria to produce polyesters, and discovered PHB. It was, however, overlooked and forgotten as the need of such biopolymer at the time was unneccesary.
In 1957, PHB was rediscovered in Britain and USA. Further development and research was conducted during the 1960's.
The mass production of PHB began after the 1990's because of the growing need of a environmentally friendly plastic alternative.
PHB has potential uses commercially as the cost of production is constantly decreasing.
It can be used to make disposable food containers (High MP, biodegradable); surgical pins (durable, Melt processable, biodegradable, so that it will dissolve after surgery); Controlled drug carriers (biodegradable); plastic bags and cling wrap (when plasticiers are added - malleable, durable, biodegradable)
It can be seen that PHB can be used in various application, however its properties are similar to those of polypropylene, but is much much more costly and time-consuming to produce on a large scale due to the microbacteria technology required to manufacture it. It is also very brittle without additives, which makes it even more expensive to produce.
Hope it helps.