In grade 5, students determined the meaning of general academic and domain-specific words and phrases related to grade level subject matter. In grade 6, they also determine figurative, connotative, and technical meanings of words and phrases. In grade 7, they will continue to do the same, and they. will also analyze the impact of a specific word choice on meaning and tone.
Written by Anne Reagan. May 13, 2014. Polybutylene piping is a form of plastic resin and was commonly used for plumbing U.S. homes built between 1978 and 1995. Due to its inexpensive production cost and ability to withstand high water pressure, it was widely seen as a better, cheaper alternative to copper plumbing.
Polybutylene (polybutene-1, poly(1-butene), PB-1) is a polyolefin or saturated polymer with the chemical formula (C4H8)n. It should not be confused with polybutene, a low molecular weight oligomer. Polybutylene is produced by polymerisation of 1-butene using supported Ziegler-Natta catalysts. PB-1 is a high molecular weight, linear, isotactic, and semi-crystalline polymer. PB-1 combines typical characteristics of conventional polyolefins with certain properties of technical polymers.