DD208470A3 - METHOD FOR PRODUCING POLYMERIC KV STABILIZERS - Google Patents

Abstract

Process for the light stabilization of polymers by admixing polymeric UV stabilizers. The aim and object of the invention is to produce light-stabilized polymers by admixing high molecular weight UV stabilizers. The polymeric UV stabilizers are said to be stable to hydrolysis, preferably to be on the surfaces of the polymers to be protected, to be largely compatible with them and not to be volatilized in the thermal treatment of the protected polymers. According to the invention, this object is achieved in that initially polymeric UV stabilizers are obtained by terminating anionically produced "living" polyolefins or polyolefin-polydimethylsiloxanes with acyloxy- or halosilanes or siloxanes containing halogenpropyl groups and subsequently polymer-analogous nucleophilic substitution reactors with hydroxyl-containing UV stabilizers having hydroxyl-containing UV stabilizers. Stabilizers produced and the thus obtained high molecular weight UV stabilizers other polymers are admixed.

Description

Process-on preparation of .polymer UV stabilizers

Field of application of the invention

The invention relates to a process for the preparation of high molecular weight UV stabilizers «The mentioned

L '(A) _n η = 1 - 3 (L ¹ Af _n

or block copolymers

• L «(AB) _n η = 1 - 3 A (3LOo

wherein L '= üv stabilizer residue-containing silane or:

Silosan

A = polyolefin block 3 = polysiloxane block

mean and the used breaker L in the Hegel of the following Pornel suffices:

, ₂ .

9 ^ Q

34

^Γ 3

1 with R =

HalogenOropylrest, the part-3

I ₁

_{> Ρ} 2 be replaced by R- '

can

R = hydrolytically cleavable group, e.g. Halogen, Acylo: iyreste R ^ = alkyl or aryl radical

Analog. Trifunctional silane compounds or with only one hydroIysierbaren group can be used in the same Yieise * L ^f In the HaIogenatome the Halogenpropylreste warden DES terminator by means of a polymer-analogous nucleophilic substitution reaction by UV stabilizer residues. (eg 2-hydroxybenzphenol ~ 4-osyreste) replaced *

Characteristic of the known technical solutions

In the art, the light stabilization of poisons is usually accomplished by physical admixing of UV stabilizers, such as "B" dihydrosybenzophenone ether. However, due to the high volatility, the applied substances are prone to significant thermal processing. Measures to 'sweat out. Therefore, attempts have been made to develop less volatile higher molecular weight compounds or to link the UV stabilizer to the polymer to be protected via covalent bonds. Sine technical solution? Mrda in the synthesis of higher molecular weight compounds, such as * 3 *

R.

^ f ^ 3.352.986)

Aryl, alkyl radical

QH

1-12

* Principally similar compounds are described by Sergeev, V * A "in Others in Vysokoincl.Soedin, 3 * A 22 0 977) 7, 1926-31, but the Si-OC bonds are.

Mi-W '/ a

Not hydrolysis-stable- Oaher low-molecular fragments of the protected compounds are formed in the presence of atmospheric moisture, which have a similar high volatility, as the o.g. Lihydrosybenzophenone Ethers »As higher molecular mass, silicon-free UV stabilizers u, a. Compounds of the 'type

R: H, OH

R ¹ R ² : C _1-12 alkyl, alkoxy

[Japan 76 9O ₃ 329; Czech ". 159 526, Mazur, Ξ *, Lewandowska, I *; Rocz.Panstw.Inkl.Mig · 27 (1976) 6, 611-19] and a bisphenol-A-2, 4-dihydros: 2 / benzophenone-phosgene Copolytaer (Japan 77 03, 639) have become known, sine particularly high Compatibility of the stabilizer with the polymer is achieved if the UY stabilizer contains the same monomer units as those polymers. Ss, therefore, suitably substituted UV stabilizers have been copolymerized with the monomer from which the polymers to be protected are also made Patent Hr 75 20, 059, the copolymerization of the compound

Protected with other monomers in a similar manner, the compound 2, 4-dihydrosy-4 '- "inyl-benzophenone copolymerized in styrene in a free-radical form (0,7ogl, Pure Appl.Chein * H (1979) 2409-241 ^ In the same publication Another possibility of solid anchoring of UVr stabilizers in polymers is the esterification of 4- (2-bromoethoxy) -2-h; rdro3-r-bensophenone with Pcly (tetra-butylammonium methacrylate).

? ^H 0

COCTNBu,

The proportion of said polyarranated or higher molecular weight UV stabilizers is that they are present only to a small extent on the surface of the polymer where they have their main activity, ie a large part of the ÜY stabilizer contained in the polymer remains' ineffective * Overcoming this disadvantage, the authors achieve, the patents DS OS 2.-346-419, US 3-341 * 49; by applying a ÜY stabilizer-containing coating after the deformation, the polymer * This ensures that the UV stabilizer is on the surface of the polymer. A disadvantage is that even with low mechanical abrasion of the UV stabilizer is completely lost ..,

Another possibility is the covalent binding of the

Stabilizer 'via a Polysilosanrest on aas polymer ,, (WP G 03K / 239 133/6). The ridiculous part of this method is that the stabilizer incorporation is bound to a certain manner of representation (eg, anionic polymerization). In most cases, however, the polymers which protect the polymer are produced by radical polymerization of the monomers. It is known that polyolefin-polysiloxane copolymers preferentially migrate into the surface layers in polyolefins, so that the outer layer of a polystyrene containing polystyrene-polydimethyisiloxane copolymer is composed of pure polydimide.

π ο ο /

-5- <LU - ^) $ O & 4

methylsiloxane (Clark, DT *; Dilke, A "; Peeling, J .; Thomas, HR; Faraday Discuss. Chem. Soc. 6Q (1976) 183-95) *

Object of the invention

The aim of the invention is to obtain non-volatile, hydro-stable, polymeric UV stabilizers which are well compatible with the polymer to be protected and ensure that the UV stabilizer residues are preferably concentrated in the surface layers small amount of UV stabilizer a maximum Lichtschutζ the polymers can be achieved »-

Explanation of the essence of the invention

The object of the invention is to produce high molecular weight UV stabilizers which are as far as possible compatible with the polymer to be protected, stable to hydrolysis and non-volatile, and are preferably present in the surface layers.

According to the invention, the object is achieved in that UV-stabilizer bilisatorhaltige polymers ⁷ :; which consist of a polyolefin or, polyolefin-polydimethylsilosian, since silane or siloxane residues containing UV stabilizer groups The process of the invention for preparing the other polymers of miscible polymeric UV stabilizers consists in an anionic polymerization or copolymerization

j

of olefins or olefins and cyclic siloxanes and the termination of the polymerization with reactive halogenpropylgruppenhaltigen silicon compounds ^ By subsequent polymeranalcge nucleophilic substitution of the halogen atoms of the halopropyl groups hydroxyl-containing UY Stabilisatcrreste be introduced. The anionic polymerization is preferably carried out in aprotic (ζ.3 "hexane) or aprotic dipolar solvents (s, 3., Tetrahydrofuran ™

- ⁶ - L Ü Ό 3 <J

at -80 to +50 ⁰ C.

The initiator organometallic compounds of the 1.

to 3 »main group of the periodic table (for example, Li-alkyls) or alkali metal aromatics (ζ · Β * Na- or K-! Taphthalin) used.

In the polymerization or copolymerization of olefins _such} * B * styrene, butadiene or acrylonitrile, arise PoIymeranionen C or dianions C * "* nnerisation When COOOL ^

ß. n.

Depending on the initiator used, the olefins with cyclic siloxanes, such as S, B, hexamethylcyclotrisilosanes (D_) or octaneethylcyclotetrasiloxane (D.), are polyanionic anions of the type AB "or *" BAB ", (Ai polyolefin, 3: polysilosane) with silane latex groups * These polymer xaono- or -dianions break down at elevated temperature with mono-, di- or trifunctional halogen-containing silicon compounds as breakers. The halopropyl groups are then reacted in a polymer-analogous nucleophilic substitution reaction by UY stabilizer radicals (. Hydro3: ybenzophe.non-4-oxyreste) replaces', which gives rise to products of the general formulas:

L ¹ (AB) _n . - n = 1 - 3

', DZW.

A (L ^f ) p --- (BL ¹ J ₉ L ¹ = UY-3 "cabilisator-

- Silane or siloxane (L ¹ A) ₇₁ (L ¹ BAB) rest A = polyolefin in block

B = polysiloxane block In order to obtain the silicon terminator of the general formula according to the invention

'I' RK = 'HQ ι QfforirjroOir! T ¹ ^ c; -r ft Ci- "

I! i i p

• d2! π _Α ο! - ^ - p2 can be replaced by R

-0.L-U-D-L-JX ρ

-2

= hydrolyzable;

-1/ --

n = 0-20

O 1 Q 1 O / /

halo or acyloxyhydrogensilanes are added to the G = C double bond of allyl halides by known methods. The described silicon compounds can be hydrolyzed partially with a water-solvent mixture to oligo- or polysiloxanes with hydrolyzable end groups. The "living" polymer chains broken off with the halogenated silanes or silanes described above are broken off. The polymer-analogous nucleophilic reaction of Co-polymers containing cosolpropyl groups with UV stabilizers containing hydrosyl groups with the formation of GOG bonds also take place by known methods. Advantages of the method according to the invention are the volatility of the UV stabilizer added, its hygroscopic properties.

LLX O ^. j OCO

and the enrichment of the stabilizer on the surface of the polymer »

The advantages mentioned represent a technical Portschrit 'of the previously known Lösunsren.

Au s τ "15" ¹ ^ " ¹ ^ Un '-z sbeis ό i ^" 5 e

Example 1 Preparation of polybutadiene of the type L '(A) p

30 g (0.55 mol). Butadiener rerden with 0.96 g (1.5-1O " ² mol) of n-3uty! Lithium (dissolved in 14» 3 ^ l of Hesan) as an initiator in hexane at 50 C under inert conditions anionic polymerized, Then with the For the work-up, the polymer is precipitated from the solution with methanol and reprecipitated with methanol, then the polymer is dissolved in 100 ml of TFA ( tetrahydrofuran) and then it is dissolved in 100 ml of tetrafluoranilane. · O · (0.01 mol) of 2,4-dihyaro ^ benzophenone soya Ig S ₀ GO, in 300 ml of DM? (Dimethylformamide) SO min heated to 120 ⁰ G.

For workup, the PolymerIosung with; Methanol precipitated and again umgeiällt, The polymer is dried for a week in a vacuum oven.

I _n : 3900

% By weight of stabilizer: 5.5

The UV stabilizer described is particularly suitable for the stabilization of polybutadiezihaltigen polymers. "" To produce small amounts of stabilized polymers, the appropriate amount of high molecular weight uV stabilizer together with polybutadiene in a vibrator to M *?. Irdenne mixed "Pur larger quantities are suitable all known mixing methods ..

Example 2: Preparation of polybutadiene-polydimethylsiloxane copolymer of the L '(AB) ρ type

37.4 g (0.6.9 mol). Butadiene are anionic polymerized with 1.19 g (1.37 * 10 "'" mol) of n-butyllithium (dissolved in 17.3 ml of hexane) as an initiator in hexane at 50 ⁰ G under inert conditions. Subsequently, 17.5 S (0.078 mol) Hezamethylcyclotrisiloxan (D-,) dissolved in 50 ml of THP is added, Hach ended copolymerization is stopped as in Example 1 and worked up * Then the copolymer is dissolved in 100 ml of THP and with 4.4 g (0.02 mol)

and 1.85 g K ^ CO-> in 400 ml DuD?

Heated to 120 ⁰ C for 90 min. For workup, the polymer solution is precipitated methanol, admixed with Heican to remove homopolysiloxane, and again circulated, drying see Example 1, admixture see Example 1 »

i "..: 5600

^ ~ Wt% 3.3 wt Stabilisatori "-% Si;. 6.7 ".

• jj / α '- ^l

Example 3 ·: Preparation of Type A (L ') Polystyrene ₉

15.64 g (0.15 MoI) are styrene with 0.21 g _(1} 26 * 10 ^-3 MOI) K-laphthalin (dissolved in 1 ml of THP) as the initiator in thir at -78 ⁰ C under inert conditions anionically polymerized ,, Subsequently, with chlorpropylhaltigem terminators, prepared by addition of Dirnethylchlorliydroge: aborted cs Ilan of allyl chloride _workup} * see example 1 "Subsequently, the polymer is dissolved in 100 ml of THP and 1.4 g (6 ^e 10 moles). 2 , 4-Dihydrosybensophenon and 1 g KpOO-in 150 ml of DMF SO min heated to 120 ⁰ G. For work-up, see Example 1 »For mixing, see Example I»,

EL ₁ : 25 200

Wt -% UV stabilizer. 1.7 vj-ew. -70 01: \ 3

Example 4 Preparation of Polystyrene-Polydimethylsiloxane Type A (BL ') Copolymers

15.64 g (0.15 mol) of styrene are treated with 0.21 g (1.26 * IC * ™ ³ mol) of K ~ Uaphthaiin (dissolved in 1 ml THF) as initiator in THF at -78 ⁰ C under inert conditions anionically polymerized "Subsequently B end"'"ground I5,64 g (Q> 07 mol) Hemamethylcyclotri-

Tach ended copolymerization is made with chloropropyl-containing Abbruch by addition of DirnethySchiorsiian to allyl chloride, stopped * For workup, the polymer solution is precipitated with methanol, added hexane to homopolysilicane dissolve out, and reprecipitated, reaction

;, 4-Dihydroxybenesophenone and work-up, see example For example, see BeisOiel 1 _Λ

u-% Si: 18, p

ϊ .-% UT stabilizer: 0.42

The in Examples 3 ^U -Q. 4 "described uV-Stabilisa -or ownei

especially Sta ~ ο.τ stabilization τοπ poly-

styrenic polymers ^

Claims (1)

Preparation of polymeric light stabilizers, characterized by aa3 hydrolysis-stable, non-volatile, compatible with the polymers to be stabilized and surface-enriching UV-sts.bilisa.torgriiD-penhaltige polymers by anionic polyinerization of olefins osv / * block copolymerization of olefins and cyclic siloxanes , Termination of the polymerization with halogen-containing reactive silicon compounds and subsequent linkage with hydro ^ Igruρpenhaltigen ÜY stabilizers in a polyseranalogen nukiec philen substitution reaction to form COC bonds won-