JPS61126106A - Modification of vinyl chloride resin - Google Patents

Abstract

PURPOSE:To obtain a modified vinyl chloride resin useful for transparent cases and packaging materials which must be antistatic, by reacting a vinyl chloride resin with an organophosphine. CONSTITUTION:100pts.wt. vinyl chloride resin of a chlorine content of 50-70wt% is reacted with 0.01-100pts.wt. organophosphine of the formula: PR3 (wherein R is alkyl or aryl). Organophosphines having a basicity, pKa, >=7 are selected desirably because of their reactivity. Especially, basic substituted triphenylphosphines higher than piperidine (pKa of 11.2) in basicity are desirable because they are highly reactive and can be easily handled because of being solid and odorless. When the amount of the organophosphine added is below 0.01pt.wt., the property of the resin can not be modified while when it is above 100pts.wt. the decomposition reaction of the resin occurs. The obtained modified vinyl chloride resin is transparent and has a volume resistivity of about 10<8>OMEGA/cm.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method of reacting a vinyl chloride resin with an organic phosphine to chemically modify the vinyl chloride resin and impart a new function to the resin.

[Prior art]

Conventionally, methods of modifying resins after polymerization have been known in order to impart new functions to resins. Special Public Service 1971-1971
Publication No. 1, JP-A-47-83894', JP-A-Sho.48
Publication No. 591509 describes an example in which polyethylene resin was modified by silane crosslinking in a post-process to improve heat-resistant shape retention.

On the other hand, it is generally known that organic phosphites are mixed with organic phosphite resins and used as stabilizers. The method was unknown.

[Purpose of the invention]

The present invention was developed through research aimed at obtaining a modified vinyl chloride resin in which organic phosphine was chemically reacted with vinyl chloride resin. The inventors obtained the knowledge that organic phosphines are chemically bound to halogen-containing resins by reacting them by methods, etc., and further conducted various studies to complete the present invention.

[Structure of the invention]

The present invention uses an organic phosphine represented by the general formula PR3 (R consists of either an alkyl group or an aryl group or both) for a vinyl chloride resin 1 (30 parts by weight) having a chlorine content of 50 to 70% by weight. This is a method for modifying vinyl chloride resin, characterized in that the reaction is carried out at a ratio of 0°, 0.01 to 100 parts by weight.

The vinyl chloride resin used in the present invention has a chlorine content of 50 to 70% by weight, preferably 56 to 68% by weight, such as the commercially available Sumilit SX-11 (Order Chemical).
Nihoriy ) SL <fy :/) PVCTK-10
00 (Shin-Etsu Chemical) and post-chlorinated vinyl chloride resin M
-51F (water coating chemistry) etc. are used. Post-chlorinated vinyl chloride resin wire, which is made by further chlorinating vinyl chloride resin to increase the chlorine content to 57 to 70% by weight, has improved heat resistance and flame retardancy. In organic phosphine, when expressed as PH1, R is an alkyl group (-(CHz)nC2(s (n
= O~20) and those with substituents on their main chains, and cyclic alkyl groups (cyclohexyl groups, etc.)
, an aryl group [phenyl group, substituted phenyl group] or both, preferably one having a basicity pka of 7 or more is selected from the viewpoint of reactivity.

However, when PR3+H" ≠HP+R3, pk@=
tog Strongly basic substituted triphenylphosphine (British Chemical Journal J, C, S, r Chem, Corrrun
, + 482 + 1984) are preferred because they have high reactivity, are solid, have no odor, and are easy to handle.

However, it is believed that the alkoxy group at the 2, 4, and 6 positions of the phenyl group greatly contributes to the basicity and reactivity of the phosphine by donating electrons. These organic phosphines cause a halogen atom substitution reaction with the halogen-containing resin as described below, and as a result, the organic phosphine chemically bonds to the polymer chain and forms a cation and υ-substituted halogen anion and phosphonium salt. All these findings have led to the present invention. The resulting resin had significantly reduced electrical resistance and was transparent. When PRs with a sterically bulky R are used, the molecular structure of the resin changes, making it possible to control gas permeability.

0.0% organic phosphine was added to 100 parts by weight of vinyl chloride resin.
01 to 100 parts by weight, preferably 1 to 10 parts by weight, are heated at 140°C by a conventional method using a roll, single screw extruder, twin screw extruder, etc.
By melt-kneading and granulating at ~180°C, modified vinyl chloride resin pellets are obtained. Organic phosphite/ is 0.0
If the amount is less than 1 part by weight, the physical properties of the resin will not change;
Above parts by weight, a decomposition reaction of the resin occurs.

The melt-kneading is preferably carried out under an inert gas stream to prevent oxidation and side reactions of the organic phosphine. Further, inorganic fillers not containing organic halides, glass fibers, carbon fibers, lubricants, stabilizers, flame retardants, plasticizers, other resins, etc. may be melt-kneaded at the same time.

In the solution reaction method, vinyl chloride resin is dissolved in an organic solvent such as benzene or tetrahydro7ran, and the organic phosphine is added thereto, and the mixture is heated at a temperature of 60°C to 200°C under normal pressure or increased pressure while stirring. Let it react for at least 2 hours.

At this time, it is preferable to carry out under an inert gas stream. By granulating according to the pressure after the reaction, modified vinyl chloride resin pellets are obtained.

Also, a film of modified vinyl chloride resin can be obtained directly by casting.

In the dipping method, an appropriate amount of organic phosphine is dissolved in advance in an organic solvent that swells vinyl chloride resin, such as benzene, tetrahydrofuran, or ethanol, and a vinyl chloride resin molded body or film that has been molded into a required shape is used to dissolve the organic phosphine. A modified vinyl chloride resin molded article or film can be obtained by immersing it in a solution at room temperature for 1 hour or more and then drying it at 100° C. or higher for 30 minutes or more. Even in this method,
It is preferable to carry out under an inert gas flow.

[Effects of the Invention] According to the present invention, the organic phosphine is chemically bonded to the polymer chain of the vinyl chloride resin to form a phosphonium salt. This phosphonium salt will not be eluted by washing with water or the like, and will not change over time. The obtained modified vinyl chloride resin is transparent and exhibits a volume resistivity of about 109Ω, so it can be used for transparent IC tray cases, medical packaging, and food packaging that require antistatic properties.

〔Example〕

Examples 1 to 4 100 parts by weight (100P) of Nivolit SL (Chisso), 1 part by weight of octyltin, 1 part by weight of calcium stearate, and 5 parts by weight of tris(2,4,6-drimethoxyphenyl)phosphine t-0,01 color After mixing at 170°C for 3 minutes with a adding roll, the resulting resin was heated at 170°C.
A sheet sample with a thickness of 15 wm was obtained by press molding. The volume resistivity and antistatic effect of this were measured using an honest meter. The results are shown in Table-1.

Example 5 Post-chlorinated vinyl chloride resin HA-51F (Made by Block Chemical, chlorine content 68% by weight) 100 parts by weight octyltin 1 part by weight and 1 part by weight calcium stearate were rolled together and press-molded to form a sheet sample.) This was immersed in a 5% benzene solution of tris(2,6-cymethoxyphenyl)phosphine at room temperature, left for 2 hours, then taken out and dried at 100°C for 1 hour.The results are shown in Table 1.

Example 6 The sheet sample obtained in Example 3 was washed with soapy water and the antistatic effect was measured using an honest meter. It is shown in Table-1.

Example 7 The same procedure as in Example 3 was carried out using triphenylphosphine as the organic phosphine.

It is shown in Table-1.

Comparative Example 1 Nipoly) SL (Chisso) 100 parts by weight (1
00f) was added with 2 parts by weight (2 t) of an organic phosphite (triphenylphosphite, Ishizu Pharmaceutical Co., Ltd.), and the same procedure as in Examples 1 to 4 was carried out. It is shown in Table-1.

Comparative Example 2 Medium viscosity polypropyref 100 parts by weight (10
In the same manner as in Examples 1 to 4, 1 part (2f) of tris(2,4,6-rimethoxynydiphenyl)phosphine t-2 was added to 0r).

Note 1) p (2, 4, 6) 3 = ) squirrel (2, 4,
6-)rimethoxyphenyl)phosphine p (2,6)3= )lis(2,6-simethoxyphenyl)phosphine pph3=triphenylphosphine Note 2) Applied voltage 10 KV, application time 30 seconds Patent applicant
Sumitomo Bakelite Co., Ltd. Masanori Wada

Claims (1)

[Claims] Vinyl chloride resin 100 with a chlorine content of 50 to 70% by weight
Vinyl chloride characterized by reacting an organic phosphine represented by the general formula PR_3 (R consists of either an alkyl group or an aryl group or both) at a ratio of 0.01 to 100 parts by weight based on parts by weight. Modification method of resin.