Abstract: The present disclosure relates to a polymer composition, and belongs to the technical field of PVB plasticizers. The polymer composition includes PVB and plasticizer, wherein the plasticizer has a structure as shown in a formula 1a or 1b; 1a R1-(C6H4)—(—OCH2CH2—)n—OH; 1b R2-(-OCH2CH2—)n—OH; wherein, n is an integer ranging from 2 to 30; R1 is C6-C16 aliphatic hydrocarbyl; and R2 is saturated or aliphatic hydrocarbyl having 12 to 20 carbon atoms in a linear carbon chain form. An elongation at break is a sign of softness, and it has been discovered through experimental study in the present disclosure that a substance with the structure as shown in the formula 1a or 1d has significant advantages relative to 3G8 when used as a PVB plasticizer, which is mainly reflected in the significant increase in the elongation at break.

Abstract: A test system for measuring the gas permeation parameters of an ultra-low permeability medium in multi-field and multi-phase coupling conditions, comprising a triaxial permeation chamber, a deformation monitoring apparatus, a temperature sensing control apparatus, a volume/pressure controller, a bias stress loading apparatus, a gas injection apparatus, an outlet buffer container, and an ultra-low permeation flow monitoring apparatus. During the test, first applying temperature and triaxial stress control to a rock-soil mass sample; using the gas injection apparatus to inject high-pressure gas into the rock-soil mass sample; after permeation, the high-pressure gas enters the outlet buffer container and the ultra-low permeation flow monitoring apparatus to acquire the gas permeation flow; and, in the test process, the deformation monitoring apparatus can measure the local absolute deformation of the rock-soil mass sample.

Abstract: A test system for measuring the gas permeation parameters of an ultra-low permeability medium in multi-field and multi-phase coupling conditions, comprising a triaxial permeation chamber, a deformation monitoring apparatus, a temperature sensing control apparatus, a volume/pressure controller, a bias stress loading apparatus, a gas injection apparatus, an outlet buffer container, and an ultra-low permeation flow monitoring apparatus. During the test, first applying temperature and triaxial stress control to a rock-soil mass sample; using the gas injection apparatus to inject high-pressure gas into the rock-soil mass sample; after permeation, the high-pressure gas enters the outlet buffer container and the ultra-low permeation flow monitoring apparatus to acquire the gas permeation flow; and, in the test process, the deformation monitoring apparatus can measure the local absolute deformation of the rock-soil mass sample.