TH9362B - Extruded polypropylene polymer resin foam - Google Patents

Abstract

Extruded polypropylene polymer resin foam It consists of a propylene polymer resin that exhibits at least a biaxial expansion viscosity of 3.0 x 10 tha point at the biaxial expansion stress 0.2 and the coagulation rate. The Stress in two alpha axes, at least 0.25, the coagulation rate with alpha stress was determined with the following formula: alpha = 0.77 x (log e 2 - log e 1) where eta 1 represents the Viscous expansion in two axes At the biaxial expansion stress 0.01 and e ta e represent the biaxial expansion viscosity. At the stress of Expanded in two cores 0.2 foam. This is a lot of cells. The thickness is at least 20 mm, the density from 0.005 to 0.03 g / cm 3, the average cell diameter from 0.4 to 2.0 mm, and the closed cell ratio of at least 80%. Its weight is light but also exhibits high shock-absorbing operation and excellent mechanical strength. The resulting foam resin can be used effectively. In the range of anti-shock packaging materials, floating materials and thermal insulation materials

Claims (1)

1.Foam of extruded polypropylene polymer That contains many closed cells That is defined by the cell wall Which makes up the matrix of the said foam The matrix consists of a viscous polypropylene resin. Ejector in two axes The coagulation rate was at least 3.0 x 10 theta point at 0.2 biaxial expansion stress and at least 0.25 in biaxial stress coagulation rate. With the following formula, alpha = 0.77 x (log e 2 - log e 1) where eta 1 represents the biaxial expansion viscosity. At stress expansion The biaxial ejector 0.01 and eta e represent the biaxial expansion viscosity at the biaxial expansion stress 0.2, where the foam has a thickness of at least 20 mm, density from 0.005. To 0.03 g / cm 3, average diameter from 0.4 to 2.0 mm, and the closed cell ratio of at least 80%, where the closing ratio is defined as a percentage. Of the volume of closed cells Compared with the total volume of cell and open cells in that foam 2. Foam according to claim 1 with a thickness of at least 30mm 3. Foam according to claim 1 with a minimum J1 of peak acceleration 80G Or less, obtained sequentially by pre-determined numbers of different weights in the tare One weight release exam Which are pre-determined numbers of different weights that can be vehicle Given, respectively, different stationary stresses in the range from 0.02 to 0.4 kgf / cm 2 on the foam was applied. And weights were separated, released one at a time, from a height of 60 cm onto the foam to achieve peak acceleration. Related to stationary throttle, where J1 is defined as the minimum value of peak acceleration. Where the minimum is read from the smooth curve obtained by drawing the peak acceleration line to the stationary stress 4. foam according to claim 1 with a value of 1.5 or less as a reduction index. The operation was performed as a cushioning K, defined by the formula K = J AV / J1, where J1 was defined in claim 3 and JAV was obtained by testing. Four identical weights are released as set out in claim 3 after the test. One such weight release It was the first weight release test, resulting in 4 peak acceleration values in the 2nd to 5th release test. Address related to each other Calculate the mean peak acceleration with the associated stationary stress. And read the minimum JAV value of the average peak acceleration from the smooth curve obtained by the stroke The mean peak acceleration to stationary stress 5. The foam according to claim 1 with the performance index K, as defined in claim 4, is 1.3 or less. Holds 1 with at least 95% of the thickness returned after R compression, obtained by applying pressure to the foam in a direction along its thickness at a rate of 500 mm / min to compress the foam by That is 90% of the initial foam thickness. Foam release from compressive strength and set the emitted temperature from that strong substance for 24 cm and the foam thickness is restored and the returned foam thickness is measured where R is defined as a percentage. Foam thickness returned 7. Foam according to claim 1, the anisotropy of Z compression stress is 1.5 or less. 8. Foam according to claim 1, where propylene polymer The resin is a linear polymer 9. Foam, in accordance with claim 1, where the propylene polymer is Contains ethylene in the amount of 0.05 to 8% by weight of 1.0 foam according to claim 1, where such polyphenol polymers have an inflation index S of 1.8 or more. This was obtained by extruding the polypropylene polymer resin in a molten form in a vertical direction at 650 s-1 tear attenuation across narrow-lined tubes. 2.095 mm inner diameter and 8.0 mm length to form a strip extruder. Length in this way, where S is defined as the proportion of the diameter of the extruded substance. Let's connect the inside diameter of the narrow tube 1. 1. Foam according to claim 1, where the said propylene polymer resin The mean molecular weight Z is at least 2 x 10 th and the Mz / Mw value is at least 5, while Mz and Mw are numbers of mean molecular weight Z and mean molecular weight respectively weighted by each value. With gel permeate chromatography