Method for preparing a synthetic resin filament in a melt blowing process from rheological properties of the synthetic resin

Patent metadata

Field	Value
Publication number	US-10976229-B2
Application number	US-201716090732-A
Country	US
Kind code	B2
Filing date	Aug 31, 2017
Priority date	Oct 17, 2016
Publication date	Apr 13, 2021
Grant date	Apr 13, 2021

Abstract

The present invention relates to a method for predicting the break-up possibility of a synthetic resin filament in a melt blowing process from the rheological properties of the synthetic resin. According to the present invention, a method that is capable of predicting the break-up possibility of the synthetic resin filament in the melt blowing process for preparing a filament using the synthetic resin in advance, through the measurement of the rheological properties of the synthetic resin, is provided.

First claim

The invention claimed is:

1. A method for preparing a synthetic resin filament, comprising:
applying 200% strain to a synthetic resin sample at 235° C., and then measuring a change in residual stress with passage of time;
confirming whether or not the change in residual stress fulfills the following Mathematical Formula 1:
(RS 1 /RS 0 )*100≤0.04  [Mathematical Formula 1]

wherein, in Mathematical Formula 1,
RS 0 is residual stress at one time point (t 0 ) of less than 0.05 seconds after applying 200% strain to the synthetic resin sample at 235° C., and
RS 1 is residual stress at one time point (t 1 ) between 0.05 seconds and 1.50 seconds after applying 200% strain to the synthetic resin sample at 235° C.; and
conducting a melt blowing process using a synthetic resin sample fulfilling the Mathematical Formula 1 to prepare the synthetic resin filament.

2. The method for preparing the synthetic resin filament according to claim 1 , wherein in the Mathematical Formula 1, t 0 is 0.02 seconds and t 1 is 1.00 seconds.

3. The method for preparing the synthetic resin filament according to claim 1 , wherein the synthetic resin sample fulfilling Mathematical Formula 1, has properties fulfilling the following Mathematical Formula 2:
( M w *10 −5 )*(MWD 0.5 )≤3.0  [Mathematical Formula 2]

wherein, in Mathematical Formula 2,
Mw is the weight average molecular weight of the synthetic resin (g/mol),
MWD is the molecular weight distribution of the synthetic resin.

4. The method for preparing the synthetic resin filament according to claim 1 , wherein the synthetic resin sample fulfilling Mathematical Formula 1 has properties fulfilling the following Mathematical Formula 3:
HMW≤2.5  [Mathematical Formula 3]

wherein, in Mathematical Formula 3, HMW is a content (wt %) of the polymer having a molecular weight (M, g/mol) of log(M)≥5.9.

5. The method for preparing the synthetic resin filament according to claim 1 , wherein the synthetic resin sample is polypropylene.

Assignees

• Lg Chemical Ltd

Inventors

• Lee Hyun Sup
• Lee Ki Soo
• Jeon Sang Jin
• An Sang Eun
• Lee Myung Han
• Park Hee Kwang
• Kim Sang Eun
• Lee Sang Hoon

Classifications

• B29C49/78 Primary

  Measuring, controlling or regulating · CPC title

• G01N2011/004

  Stress relaxation time · CPC title

• G01N11/14

  by using rotary bodies, e.g. vane (G01N11/16 takes precedence) · CPC title

• G01N2011/0033

  Yield stress; Residual stress at zero shear rate · CPC title

• G01N11/00 Primary

  Investigating flow properties of materials, e.g. viscosity, plasticity; Analysing materials by determining flow properties · CPC title